Live video camera calibration class with OpenCV an OpenCV calibration. More...

#include <CVCalibration.h>

Public Member Functions
	CVCalibration (CVCameraType camType, string computerInfos)

	CVCalibration (const cv::Mat &cameraMat, const cv::Mat &distortion, cv::Size imageSize, cv::Size boardSize, float boardSquareMM, float reprojectionError, int numCaptured, const string &calibrationTime, int camSizeIndex, bool mirroredH, bool mirroredV, CVCameraType camType, string computerInfos, int calibFlags, bool calcUndistortionMaps)

	CVCalibration (const cv::Size &imageSize, float fovH, bool mirroredH, bool mirroredV, CVCameraType camType, string computerInfos)

	CVCalibration (float sensorWMM, float sensorHMM, float focalLengthMM, const cv::Size &imageSize, bool mirroredH, bool mirroredV, CVCameraType camType, string computerInfos)

bool	load (const string &calibDir, const string &calibFileName, bool calcUndistortionMaps)
	Loads the calibration information from the config file. More...

bool	save (const string &calibDir, const string &calibFileName)
	Saves the camera calibration parameters to the config file. More...

void	remap (CVMat &inDistorted, CVMat &outUndistorted)
	Undistorts the inDistorted image into the outUndistorted. More...

void	adaptForNewResolution (const CVSize &newSize, bool calcUndistortionMaps)
	Adapts an already calibrated camera to a new resolution (cropping and scaling) More...

void	buildUndistortionMaps ()
	Builds undistortion maps after calibration or loading. More...

CVSize	imageSize () const

CVSize	imageSizeOriginal () const

float	imageAspectRatio () const

const CVMat &	cameraMat () const

const CVMat &	cameraMatUndistorted () const

const CVMat &	distortion () const

float	cameraFovVDeg () const

float	cameraFovHDeg () const

int	calibrationFlags ()

bool	calibFixPrincipalPoint ()

bool	calibFixAspectRatio ()

bool	calibZeroTangentDist ()

bool	calibRationalModel ()

bool	calibTiltedModel ()

bool	calibThinPrismModel ()

bool	isMirroredH ()

bool	isMirroredV ()

float	fx () const

float	fy () const

float	cx () const

float	cy () const

float	k1 () const

float	k2 () const

float	p1 () const

float	p2 () const

float	k3 () const

float	k4 () const

float	k5 () const

float	k6 () const

float	s1 () const

float	s2 () const

float	s3 () const

float	s4 () const

float	tauX () const

float	tauY () const

CVCameraType	camType () const

CVCalibState	state () const

int	numCapturedImgs () const

float	reprojectionError () const

CVSize	boardSize () const

float	boardSquareMM () const

float	boardSquareM () const

string	calibrationTime () const

string	calibFileName () const

string	computerInfos () const

string	stateStr () const

Private Member Functions
void	calcCameraFovFromUndistortedCameraMat ()
	Calculates the vertical field of view angle in degrees. More...

void	calculateUndistortedCameraMat ()
	Calculate a camera matrix that we use for the scene graph and for the reprojection of the undistorted image. More...

void	createFromGuessedFOV (int imageWidthPX, int imageHeightPX, float fovH)
	Calculates camera intrinsics from a guessed FOV angle. More...

Private Attributes
CVMat	_cameraMat
	3x3 Matrix for intrinsic camera matrix More...

CVMat	_distortion
	4x1 Matrix for intrinsic distortion More...

CVMat	_cameraMatOrig
	3x3 Matrix for intrinsic camera matrix (original from loading or calibration estimation) More...

CVSize	_imageSizeOrig
	original image size (original from loading or calibration estimation) More...

CVCalibState	_state = CS_uncalibrated
	calibration state enumeration More...

float	_cameraFovVDeg = 0.0f
	Vertical field of view in degrees. More...

float	_cameraFovHDeg = 0.0f
	Horizontal field of view in degrees. More...

string	_calibFileName
	name for calibration file More...

int	_calibFlags = 0
	OpenCV calibration flags. More...

bool	_isMirroredH = false
	Flag if image must be horizontally mirrored. More...

bool	_isMirroredV = false
	Flag if image must be vertically mirrored. More...

int	_numCaptured = 0
	NO. of images captured. More...

CVSize	_boardSize
	NO. of inner chessboard corners. More...

float	_boardSquareMM = 20.f
	Size of chessboard square in mm. More...

float	_reprojectionError = -1.0f
	Reprojection error after calibration. More...

CVSize	_imageSize
	Input image size in pixels (after cropping) More...

int	_camSizeIndex = -1
	The requested camera size index. More...

CVMat	_undistortMapX
	Undistortion float map in x-direction. More...

CVMat	_undistortMapY
	Undistortion float map in y-direction. More...

CVMat	_cameraMatUndistorted
	Camera matrix that defines scene camera and may also be used for reprojection of undistorted image. More...

string	_calibrationTime = "-"
	Time stamp string of calibration. More...

string	_computerInfos

CVCameraType	_camType = CVCameraType::FRONTFACING

Static Private Attributes
static const int	_CALIBFILEVERSION = 6
	Global const file format version. More...

Detailed Description

Live video camera calibration class with OpenCV an OpenCV calibration.

The camera calibration can determine the inner or intrinsic parameters such as the focal length and the lens distortion and external or extrinsic parameter such as the camera pose towards a known geometry.
For a good calibration we have to make 15-20 images from a chessboard pattern. The chessboard pattern can be printed from the CalibrationChessboard_8x5_A4.pdf in the folder data/calibration. It is important that one side has an odd number of inner corners. Like this it is unambiguous and can be rotated in any direction.
The different calibration states are handled within AppDemoTracking::onUpdateTracking:

CS_uncalibrated: The camera is not calibrated (no calibration found found)
CS_calibrated: The camera is calibrated
CS_guessed
The core of the intrinsic calibration is stored in the members _cameraMat and _distortion. For the calibration internals see the OpenCV documentation: http://docs.opencv.org/3.1.0/dc/dbb/tutorial_py_calibration.html After a successfully calibration the parameters are stored in a config file on the SL::configPath. If it exists, it is loaded from there at startup. If doesn't exist a simple calibration from a default field of view angle is estimated.
The CVCapture instance has two video camera calibrations, one for a main camera (CVCapture::mainCam) and one for the selfie camera on mobile devices (CVCapture::scndCam). The member CVCapture::activeCamera points to the active one and is set by the CVCapture::videoType (VT_NONE, VT_MAIN, VT_SCND) during the scene assembly in AppDemoLoad. On mobile devices the front camera is the selfie camera (our secondary) and the back camera is the our main camera.

Definition at line 70 of file CVCalibration.h.

Constructor & Destructor Documentation

◆ CVCalibration() [1/4]

CVCalibration::CVCalibration	(	CVCameraType	camType,
		string	computerInfos
	)

Definition at line 30 of file CVCalibration.cpp.

   : _state(CS_uncalibrated),
     _cameraFovHDeg(0.0f),
     _cameraFovVDeg(0.0f),
     _calibFileName(""), // is set in load
     _boardSize(0, 0),
     _boardSquareMM(0.0f),
     _numCaptured(0),
     _reprojectionError(-1.0f),
     _camSizeIndex(-1),
     _calibrationTime("-"),
     _isMirroredH(false),
     _isMirroredV(false),
     _camType(type),
     _computerInfos(std::move(computerInfos))
 {
 }

◆ CVCalibration() [2/4]

CVCalibration::CVCalibration	(	const cv::Mat &	cameraMat,
		const cv::Mat &	distortion,
		cv::Size	imageSize,
		cv::Size	boardSize,
		float	boardSquareMM,
		float	reprojectionError,
		int	numCaptured,
		const string &	calibrationTime,
		int	camSizeIndex,
		bool	mirroredH,
		bool	mirroredV,
		CVCameraType	camType,
		string	computerInfos,
		int	calibFlags,
		bool	calcUndistortionMaps
	)

Definition at line 49 of file CVCalibration.cpp.

   : _cameraMat(cameraMat.clone()),
     _distortion(distortion.clone()),
     _imageSize(std::move(imageSize)),
     _boardSize(std::move(boardSize)),
     _boardSquareMM(boardSquareMM),
     _reprojectionError(reprojectionError),
     _numCaptured(numCaptured),
     _calibrationTime(calibrationTime),
     _camSizeIndex(camSizeIndex),
     _isMirroredH(mirroredH),
     _isMirroredV(mirroredV),
     _camType(camType),
     _computerInfos(std::move(computerInfos)),
     _calibFlags(calibFlags)
 {
     _cameraMatOrig = _cameraMat.clone();
     _imageSizeOrig = _imageSize;
  
     calculateUndistortedCameraMat();
     calcCameraFovFromUndistortedCameraMat();
     buildUndistortionMaps();
     _state = CS_calibrated;
 }

◆ CVCalibration() [3/4]

CVCalibration::CVCalibration	(	const cv::Size &	imageSize,
		float	fovH,
		bool	mirroredH,
		bool	mirroredV,
		CVCameraType	camType,
		string	computerInfos
	)

Definition at line 89 of file CVCalibration.cpp.

   : _isMirroredH(mirroredH),
     _isMirroredV(mirroredV),
     _camType(camType),
     _computerInfos(std::move(computerInfos))
 {
     createFromGuessedFOV(imageSize.width, imageSize.height, fovH);
     _cameraMatOrig = _cameraMat.clone();
     _imageSizeOrig = _imageSize;
 }

◆ CVCalibration() [4/4]

CVCalibration::CVCalibration	(	float	sensorWMM,
		float	sensorHMM,
		float	focalLengthMM,
		const cv::Size &	imageSize,
		bool	mirroredH,
		bool	mirroredV,
		CVCameraType	camType,
		string	computerInfos
	)

Definition at line 106 of file CVCalibration.cpp.

   : _isMirroredH(mirroredH),
     _isMirroredV(mirroredV),
     _camType(camType),
     _computerInfos(std::move(computerInfos))
 {
     // aspect ratio
     float devFovH = 2.0f * atan(sensorWMM / (2.0f * focalLengthMM)) * Utils::RAD2DEG;
     if (devFovH > 60.0f && devFovH < 70.0f)
     {
         createFromGuessedFOV(imageSize.width, imageSize.height, devFovH);
     }
     else
     {
         // if not between
         createFromGuessedFOV(imageSize.width, imageSize.height, 65.0);
     }
     _cameraMatOrig = _cameraMat.clone();
     _imageSizeOrig = _imageSize;
 }

Member Function Documentation

◆ adaptForNewResolution()

void CVCalibration::adaptForNewResolution	(	const CVSize &	newSize,
		bool	calcUndistortionMaps
	)

Adapts an already calibrated camera to a new resolution (cropping and scaling)

Definition at line 438 of file CVCalibration.cpp.

 {
     if (_state == CS_uncalibrated)
         return;
  
     // new center and focal length in pixels not mm
     float fx, fy, cy, cx;
  
     // use original camera matrix for adaptions.
     // Otherwise we get rounding errors after too many adaptions.
     float fxOrig = (float)_cameraMatOrig.at<double>(0, 0);
     float fyOrig = (float)_cameraMatOrig.at<double>(1, 1);
     float cxOrig = (float)_cameraMatOrig.at<double>(0, 2);
     float cyOrig = (float)_cameraMatOrig.at<double>(1, 2);
  
     if (((float)newSize.width / (float)newSize.height) >
         ((float)_imageSizeOrig.width / (float)_imageSizeOrig.height))
     {
         float scaleFactor = (float)newSize.width / (float)_imageSizeOrig.width;
  
         fx                    = fxOrig * scaleFactor;
         fy                    = fyOrig * scaleFactor;
         float oldHeightScaled = (float)_imageSizeOrig.height * scaleFactor;
         float heightDiff      = (oldHeightScaled - (float)newSize.height) * 0.5f;
  
         cx = cxOrig * scaleFactor;
         cy = cyOrig * scaleFactor - heightDiff;
     }
     else
     {
         float scaleFactor    = (float)newSize.height / (float)_imageSizeOrig.height;
         fx                   = fxOrig * scaleFactor;
         fy                   = fyOrig * scaleFactor;
         float oldWidthScaled = (float)_imageSizeOrig.width * scaleFactor;
         float widthDiff      = (oldWidthScaled - (float)newSize.width) * 0.5f;
  
         cx = cxOrig * scaleFactor - widthDiff;
         cy = cyOrig * scaleFactor;
     }
  
     // std::cout << "adaptForNewResolution: _cameraMat before: " << _cameraMat << std::endl;
     _cameraMat = (cv::Mat_<double>(3, 3) << fx, 0, cx, 0, fy, cy, 0, 0, 1);
     // std::cout << "adaptForNewResolution: _cameraMat after: " << _cameraMat << std::endl;
     //_distortion remains unchanged
     _calibrationTime = Utils::getDateTime2String();
  
     // std::cout << "adaptForNewResolution: _imageSize before: " << _imageSize << std::endl;
     _imageSize.width  = newSize.width;
     _imageSize.height = newSize.height;
     // std::cout << "adaptForNewResolution: _imageSize after: " << _imageSize << std::endl;
  
     calculateUndistortedCameraMat();
     calcCameraFovFromUndistortedCameraMat();
     if (calcUndistortionMaps)
         buildUndistortionMaps();
 }

◆ boardSize()

CVSize CVCalibration::boardSize ( ) const

inline

Definition at line 170 of file CVCalibration.h.

170 { return _boardSize; }

◆ boardSquareM()

float CVCalibration::boardSquareM ( ) const

inline

Definition at line 172 of file CVCalibration.h.

172 { return _boardSquareMM * 0.001f; }

◆ boardSquareMM()

float CVCalibration::boardSquareMM ( ) const

inline

Definition at line 171 of file CVCalibration.h.

171 { return _boardSquareMM; }

◆ buildUndistortionMaps()

void CVCalibration::buildUndistortionMaps ( )

Builds undistortion maps after calibration or loading.

Definition at line 344 of file CVCalibration.cpp.

 {
     if (_cameraMatUndistorted.rows != 3 || _cameraMatUndistorted.cols != 3)
         Utils::exitMsg("SLProject",
                        "CVCalibration::buildUndistortionMaps: No _cameraMatUndistorted available",
                        __LINE__,
                        __FILE__);
  
     // Create undistortion maps
     _undistortMapX.release();
     _undistortMapY.release();
  
     HighResTimer t;
     cv::initUndistortRectifyMap(_cameraMat,
                                 _distortion,
                                 cv::Mat(), // Identity matrix R
                                 _cameraMatUndistorted,
                                 _imageSize,
                                 CV_16SC2, // before we had CV_32FC1 but in all tutorials they use CV_16SC2.. is there a reason?
                                 _undistortMapX,
                                 _undistortMapY);
 #if _DEBUG
     Utils::log("CVCalibration",
                "initUndistortRectifyMap: %fms",
                t.elapsedTimeInMilliSec());
 #endif
     if (_undistortMapX.empty() || _undistortMapY.empty())
         Utils::exitMsg("SLProject",
                        "CVCalibration::buildUndistortionMaps failed.",
                        __LINE__,
                        __FILE__);
 }

◆ calcCameraFovFromUndistortedCameraMat()

void CVCalibration::calcCameraFovFromUndistortedCameraMat ( )

private

Calculates the vertical field of view angle in degrees.

Definition at line 562 of file CVCalibration.cpp.

 {
     if (_cameraMatUndistorted.rows != 3 || _cameraMatUndistorted.cols != 3)
         Utils::exitMsg("SLProject", "CVCalibration::calcCameraFovFromSceneCameraMat: No _cameraMatUndistorted available", __LINE__, __FILE__);
  
     // calculate vertical field of view
     float fx       = (float)_cameraMatUndistorted.at<double>(0, 0);
     float fy       = (float)_cameraMatUndistorted.at<double>(1, 1);
     float cx       = (float)_cameraMatUndistorted.at<double>(0, 2);
     float cy       = (float)_cameraMatUndistorted.at<double>(1, 2);
     _cameraFovHDeg = 2.0f * (float)atan2(cx, fx) * Utils::RAD2DEG;
     _cameraFovVDeg = 2.0f * (float)atan2(cy, fy) * Utils::RAD2DEG;
 }

◆ calculateUndistortedCameraMat()

void CVCalibration::calculateUndistortedCameraMat ( )

private

Calculate a camera matrix that we use for the scene graph and for the reprojection of the undistorted image.

(The following is the algorithm from cv::getOptimalNewCameraMatrix and the code is here for understanding (it does the same))

Definition at line 496 of file CVCalibration.cpp.

 {
     if (_cameraMat.rows != 3 || _cameraMat.cols != 3)
         Utils::exitMsg("SLProject", "CVCalibration::calculateUndistortedCameraMat: No intrinsic parameter available", __LINE__, __FILE__);
  
     // An alpha of 0 leads to no black borders
     // An alpha of 1 leads to black borders
     // (with alpha equaly zero the augmentation fits best)
     double alpha = 1.0;
  
     bool centerPrinciplePoint = true;
     if (centerPrinciplePoint)
     {
         // Attention: the principle point has to be centered because for the projection matrix we assume that image plane is "symmetrically arranged wrt the focal plane"
         //(see http://kgeorge.github.io/2014/03/08/calculating-opengl-perspective-matrix-from-opencv-intrinsic-matrix)
         //_cameraMatUndistorted     = cv::getOptimalNewCameraMatrix(_cameraMat, _distortion, _imageSize, alpha, _imageSize, nullptr, centerPrinciplePoint);
         //! (The following is the algorithm from cv::getOptimalNewCameraMatrix and the code is here for understanding (it does the same))
  
         double cx0 = _cameraMat.at<double>(0, 2);
         double cy0 = _cameraMat.at<double>(1, 2);
         double cx  = (_imageSize.width) * 0.5;
         double cy  = (_imageSize.height) * 0.5;
  
         cv::Rect_<float> inner, outer;
         getInnerAndOuterRectangles(_cameraMat,
                                    _distortion,
                                    cv::Mat(),
                                    _cameraMat,
                                    _imageSize,
                                    inner,
                                    outer);
  
         double s0 = std::max(std::max(std::max((double)cx / (cx0 - inner.x),
                                                (double)cy / (cy0 - inner.y)),
                                       (double)cx / (inner.x + inner.width - cx0)),
                              (double)cy / (inner.y + inner.height - cy0));
  
         double s1 = std::min(std::min(std::min((double)cx / (cx0 - outer.x),
                                                (double)cy / (cy0 - outer.y)),
                                       (double)cx / (outer.x + outer.width - cx0)),
                              (double)cy / (outer.y + outer.height - cy0));
  
         double s = s0 * (1 - alpha) + s1 * alpha;
  
         _cameraMatUndistorted = _cameraMat.clone();
         _cameraMatUndistorted.at<double>(0, 0) *= s;
         _cameraMatUndistorted.at<double>(1, 1) *= s;
         _cameraMatUndistorted.at<double>(0, 2) = cx;
         _cameraMatUndistorted.at<double>(1, 2) = cy;
     }
     else
     {
         _cameraMatUndistorted = cv::getOptimalNewCameraMatrix(_cameraMat,
                                                               _distortion,
                                                               _imageSize,
                                                               alpha,
                                                               _imageSize,
                                                               nullptr,
                                                               centerPrinciplePoint);
     }
  
     // std::cout << "_cameraMatUndistorted: " << _cameraMatUndistorted << std::endl;
     // std::cout << "_cameraMat: " << _cameraMat << std::endl;
 }

◆ calibFileName()

string CVCalibration::calibFileName ( ) const

inline

Definition at line 174 of file CVCalibration.h.

174 { return _calibFileName; }

◆ calibFixAspectRatio()

bool CVCalibration::calibFixAspectRatio ( )

inline

Definition at line 139 of file CVCalibration.h.

139 { return _calibFlags & cv::CALIB_FIX_ASPECT_RATIO; }

◆ calibFixPrincipalPoint()

bool CVCalibration::calibFixPrincipalPoint ( )

inline

Definition at line 138 of file CVCalibration.h.

138 { return _calibFlags & cv::CALIB_FIX_PRINCIPAL_POINT; }

◆ calibRationalModel()

bool CVCalibration::calibRationalModel ( )

inline

Definition at line 141 of file CVCalibration.h.

141 { return _calibFlags & cv::CALIB_RATIONAL_MODEL; }

◆ calibrationFlags()

int CVCalibration::calibrationFlags ( )

inline

Definition at line 137 of file CVCalibration.h.

137 { return _calibFlags; }

◆ calibrationTime()

string CVCalibration::calibrationTime ( ) const

inline

Definition at line 173 of file CVCalibration.h.

173 { return _calibrationTime; }

◆ calibThinPrismModel()

bool CVCalibration::calibThinPrismModel ( )

inline

Definition at line 143 of file CVCalibration.h.

143 { return _calibFlags & cv::CALIB_THIN_PRISM_MODEL; }

◆ calibTiltedModel()

bool CVCalibration::calibTiltedModel ( )

inline

Definition at line 142 of file CVCalibration.h.

142 { return _calibFlags & cv::CALIB_TILTED_MODEL; }

◆ calibZeroTangentDist()

bool CVCalibration::calibZeroTangentDist ( )

inline

Definition at line 140 of file CVCalibration.h.

140 { return _calibFlags & cv::CALIB_ZERO_TANGENT_DIST; }

◆ cameraFovHDeg()

float CVCalibration::cameraFovHDeg ( ) const

inline

Definition at line 135 of file CVCalibration.h.

135 { return _cameraFovHDeg; }

◆ cameraFovVDeg()

float CVCalibration::cameraFovVDeg ( ) const

inline

Definition at line 134 of file CVCalibration.h.

134 { return _cameraFovVDeg; }

◆ cameraMat()

const CVMat& CVCalibration::cameraMat ( ) const

inline

Definition at line 131 of file CVCalibration.h.

131 { return _cameraMat; }

◆ cameraMatUndistorted()

const CVMat& CVCalibration::cameraMatUndistorted ( ) const

inline

Definition at line 132 of file CVCalibration.h.

132 { return _cameraMatUndistorted; }

◆ camType()

CVCameraType CVCalibration::camType ( ) const

inline

Definition at line 166 of file CVCalibration.h.

166 { return _camType; }

◆ computerInfos()

string CVCalibration::computerInfos ( ) const

inline

Definition at line 175 of file CVCalibration.h.

175 { return _computerInfos; }

◆ createFromGuessedFOV()

void CVCalibration::createFromGuessedFOV	(	int	imageWidthPX,
		int	imageHeightPX,
		float	fovH
	)

private

Calculates camera intrinsics from a guessed FOV angle.

Most laptop-, webcam- or mobile camera have a horizontal view angle or so called field of view (FOV) of around 65 degrees. From this parameter we can calculate the most important intrinsic parameter the focal length. All other parameters are set as if the lens would be perfect: No lens distortion and the view axis goes through the center of the image. If the focal length and sensor size is provided by the device we deduce the the fovV from it.

Parameters

imageWidthPX	Height of image in pixels
imageHeightPX	Width of image in pixels
fovH	Average horizontal view angle in degrees

Definition at line 407 of file CVCalibration.cpp.

 {
     // if (fx == fy) and (cx == imgwidth * 0.5f) and (cy == imgheight  * 0.5f)
     float f    = (0.5f * (float)imageWidthPX) / tanf(fovH * 0.5f * Utils::DEG2RAD);
     float fovV = 2.0f * (float)atan2(0.5f * (float)imageHeightPX, f) * Utils::RAD2DEG;
  
     // Create standard camera matrix
     // fx, fx, cx, cy are all in pixel values not mm
     // We asume that we have an ideal image sensor with square pixels
     // so that the focal length fx and fy are identical
     // See the OpenCV documentation for more details:
     // http://docs.opencv.org/3.1.0/dc/dbb/tutorial_py_calibration.html
  
     float cx = (float)imageWidthPX * 0.5f;
     float cy = (float)imageHeightPX * 0.5f;
     float fx = cx / tanf(fovH * 0.5f * Utils::DEG2RAD);
     float fy = fx;
  
     _imageSize.width  = imageWidthPX;
     _imageSize.height = imageHeightPX;
     _cameraMat        = (cv::Mat_<double>(3, 3) << fx, 0, cx, 0, fy, cy, 0, 0, 1);
     _distortion       = (cv::Mat_<double>(5, 1) << 0, 0, 0, 0, 0); // No distortion
     _cameraFovHDeg    = fovH;
     _cameraFovVDeg    = fovV;
     _calibrationTime  = Utils::getDateTime2String();
     _state            = CS_guessed;
 }

◆ cx()

float CVCalibration::cx ( ) const

inline

Definition at line 149 of file CVCalibration.h.

149 { return _cameraMat.cols == 3 && _cameraMat.rows == 3 ? (float)_cameraMat.at<double>(0, 2) : 0.0f; }

◆ cy()

float CVCalibration::cy ( ) const

inline

Definition at line 150 of file CVCalibration.h.

150 { return _cameraMat.cols == 3 && _cameraMat.rows == 3 ? (float)_cameraMat.at<double>(1, 2) : 0.0f; }

◆ distortion()

const CVMat& CVCalibration::distortion ( ) const

inline

Definition at line 133 of file CVCalibration.h.

133 { return _distortion; }

◆ fx()

float CVCalibration::fx ( ) const

inline

Definition at line 147 of file CVCalibration.h.

147 { return _cameraMat.cols == 3 && _cameraMat.rows == 3 ? (float)_cameraMat.at<double>(0, 0) : 0.0f; }

◆ fy()

float CVCalibration::fy ( ) const

inline

Definition at line 148 of file CVCalibration.h.

148 { return _cameraMat.cols == 3 && _cameraMat.rows == 3 ? (float)_cameraMat.at<double>(1, 1) : 0.0f; }

◆ imageAspectRatio()

float CVCalibration::imageAspectRatio ( ) const

inline

Definition at line 130 of file CVCalibration.h.

130 { return (float)_imageSize.width / (float)_imageSize.height; }

◆ imageSize()

CVSize CVCalibration::imageSize ( ) const

inline

Definition at line 126 of file CVCalibration.h.

126 { return _imageSize; }

◆ imageSizeOriginal()

CVSize CVCalibration::imageSizeOriginal ( ) const

inline

Definition at line 127 of file CVCalibration.h.

127 { return _imageSizeOrig; }

◆ isMirroredH()

bool CVCalibration::isMirroredH ( )

inline

Definition at line 144 of file CVCalibration.h.

144 { return _isMirroredH; }

◆ isMirroredV()

bool CVCalibration::isMirroredV ( )

inline

Definition at line 145 of file CVCalibration.h.

145 { return _isMirroredV; }

◆ k1()

float CVCalibration::k1 ( ) const

inline

Definition at line 151 of file CVCalibration.h.

151 { return _distortion.rows >= 4 ? (float)_distortion.at<double>(0, 0) : 0.0f; }

◆ k2()

float CVCalibration::k2 ( ) const

inline

Definition at line 152 of file CVCalibration.h.

152 { return _distortion.rows >= 4 ? (float)_distortion.at<double>(1, 0) : 0.0f; }

◆ k3()

float CVCalibration::k3 ( ) const

inline

Definition at line 155 of file CVCalibration.h.

155 { return _distortion.rows >= 5 ? (float)_distortion.at<double>(4, 0) : 0.0f; }

◆ k4()

float CVCalibration::k4 ( ) const

inline

Definition at line 156 of file CVCalibration.h.

156 { return _distortion.rows >= 6 ? (float)_distortion.at<double>(5, 0) : 0.0f; }

◆ k5()

float CVCalibration::k5 ( ) const

inline

Definition at line 157 of file CVCalibration.h.

157 { return _distortion.rows >= 7 ? (float)_distortion.at<double>(6, 0) : 0.0f; }

◆ k6()

float CVCalibration::k6 ( ) const

inline

Definition at line 158 of file CVCalibration.h.

158 { return _distortion.rows >= 8 ? (float)_distortion.at<double>(7, 0) : 0.0f; }

◆ load()

bool CVCalibration::load	(	const string &	calibDir,
		const string &	calibFileName,
		bool	calcUndistortionMaps
	)

Loads the calibration information from the config file.

Added a flag to disable calculation of undistortion maps because this may take a lot of time for big images on mobile devices

Definition at line 138 of file CVCalibration.cpp.

 {
     // load camera parameter
     string fullPathAndFilename = Utils::unifySlashes(calibDir) + calibFileName;
  
     // try to open the local calibration file
     cv::FileStorage fs(fullPathAndFilename, cv::FileStorage::READ);
     if (!fs.isOpened())
     {
         Utils::log("SLProject", "Calibration      : %s", calibFileName.c_str());
         Utils::log("SLProject", "Calib. created   : No. Calib. will be estimated");
         _numCaptured       = 0;
         _isMirroredH       = false;
         _isMirroredV       = false;
         _reprojectionError = 0;
         _calibrationTime   = "-";
         _state             = CS_uncalibrated;
         _camSizeIndex      = -1;
         return false;
     }
  
     // Reset if new file format version is available
     int calibFileVersion = 0;
     fs["CALIBFILEVERSION"] >> calibFileVersion;
     if (calibFileVersion < _CALIBFILEVERSION)
     {
         _numCaptured       = 0;
         _reprojectionError = -1;
         _calibrationTime   = "-";
         _state             = CS_uncalibrated;
         _camSizeIndex      = -1;
     }
     else
     {
         fs["imageSizeWidth"] >> _imageSize.width;
         fs["imageSizeHeight"] >> _imageSize.height;
         fs["numCaptured"] >> _numCaptured;
         fs["isMirroredH"] >> _isMirroredH;
         fs["isMirroredV"] >> _isMirroredV;
         fs["cameraMat"] >> _cameraMat;
         fs["distortion"] >> _distortion;
         fs["reprojectionError"] >> _reprojectionError;
         fs["calibrationTime"] >> _calibrationTime;
         fs["camSizeIndex"] >> _camSizeIndex;
         fs["boardSizeWidth"] >> _boardSize.width;
         fs["boardSizeHeight"] >> _boardSize.height;
         fs["boardSquareMM"] >> _boardSquareMM;
         _state = _numCaptured ? CS_calibrated : CS_uncalibrated;
     }
  
     // estimate computer infos
     if (!fs["computerInfos"].empty())
         fs["computerInfos"] >> _computerInfos;
     else
     {
         vector<string> stringParts;
         Utils::splitString(Utils::getFileNameWOExt(calibFileName), '_', stringParts);
         if (stringParts.size() >= 3)
             _computerInfos = stringParts[1];
     }
  
     // close the input file
     fs.release();
  
     // calculate FOV and undistortion maps
     if (_state == CS_calibrated)
     {
         // calcCameraFov();
         calculateUndistortedCameraMat();
         calcCameraFovFromUndistortedCameraMat();
         if (calcUndistortionMaps)
             buildUndistortionMaps();
     }
  
     Utils::log("SLProject", "Calib. loaded    : %s", fullPathAndFilename.c_str());
     Utils::log("SLProject", "Calib. created   : %s", _calibrationTime.c_str());
     Utils::log("SLProject", "Camera FOV H/V   : %3.1f/%3.1f", _cameraFovVDeg, _cameraFovHDeg);
  
     _cameraMatOrig = _cameraMat.clone();
     _imageSizeOrig = _imageSize;
  
     return true;
 }

◆ numCapturedImgs()

int CVCalibration::numCapturedImgs ( ) const

inline

Definition at line 168 of file CVCalibration.h.

168 { return _numCaptured; }

◆ p1()

float CVCalibration::p1 ( ) const

inline

Definition at line 153 of file CVCalibration.h.

153 { return _distortion.rows >= 4 ? (float)_distortion.at<double>(2, 0) : 0.0f; }

◆ p2()

float CVCalibration::p2 ( ) const

inline

Definition at line 154 of file CVCalibration.h.

154 { return _distortion.rows >= 4 ? (float)_distortion.at<double>(3, 0) : 0.0f; }

◆ remap()

void CVCalibration::remap	(	CVMat &	inDistorted,
		CVMat &	outUndistorted
	)

Undistorts the inDistorted image into the outUndistorted.

Definition at line 378 of file CVCalibration.cpp.

 {
     assert(!inDistorted.empty() &&
            "Input image is empty!");
  
     assert(!_undistortMapX.empty() &&
            !_undistortMapY.empty() &&
            "Undistortion Maps are empty!");
  
     cv::remap(inDistorted,
               outUndistorted,
               _undistortMapX,
               _undistortMapY,
               cv::INTER_LINEAR);
 }

◆ reprojectionError()

float CVCalibration::reprojectionError ( ) const

inline

Definition at line 169 of file CVCalibration.h.

169 { return _reprojectionError; }

◆ s1()

float CVCalibration::s1 ( ) const

inline

Definition at line 159 of file CVCalibration.h.

159 { return _distortion.rows >= 9 ? (float)_distortion.at<double>(8, 0) : 0.0f; }

◆ s2()

float CVCalibration::s2 ( ) const

inline

Definition at line 160 of file CVCalibration.h.

160 { return _distortion.rows >= 10 ? (float)_distortion.at<double>(9, 0) : 0.0f; }

◆ s3()

float CVCalibration::s3 ( ) const

inline

Definition at line 161 of file CVCalibration.h.

161 { return _distortion.rows >= 11 ? (float)_distortion.at<double>(10, 0) : 0.0f; }

◆ s4()

float CVCalibration::s4 ( ) const

inline

Definition at line 162 of file CVCalibration.h.

162 { return _distortion.rows >= 12 ? (float)_distortion.at<double>(11, 0) : 0.0f; }

◆ save()

bool CVCalibration::save	(	const string &	calibDir,
		const string &	calibFileName
	)

Saves the camera calibration parameters to the config file.

Definition at line 225 of file CVCalibration.cpp.

 {
     string fullPathAndFilename = Utils::unifySlashes(calibDir) + calibFileName;
  
     cv::FileStorage fs(fullPathAndFilename, cv::FileStorage::WRITE);
  
     if (!fs.isOpened())
     {
         Utils::log("SLProject", "Failed to write calib. %s", fullPathAndFilename.c_str());
         return false;
     }
  
     char buf[1024];
     snprintf(buf,
              sizeof(buf),
              "flags:%s%s%s%s%s%s%s",
              _calibFlags & cv::CALIB_USE_INTRINSIC_GUESS ? " +use_intrinsic_guess" : "",
              _calibFlags & cv::CALIB_FIX_ASPECT_RATIO ? " +fix_aspectRatio" : "",
              _calibFlags & cv::CALIB_FIX_PRINCIPAL_POINT ? " +fix_principal_point" : "",
              _calibFlags & cv::CALIB_ZERO_TANGENT_DIST ? " +zero_tangent_dist" : "",
              _calibFlags & cv::CALIB_RATIONAL_MODEL ? " +rational_model" : "",
              _calibFlags & cv::CALIB_THIN_PRISM_MODEL ? " +thin_prism_model" : "",
              _calibFlags & cv::CALIB_TILTED_MODEL ? " +tilted_model" : "");
     fs.writeComment(buf, 0);
  
     fs << "CALIBFILEVERSION" << _CALIBFILEVERSION;
     fs << "calibrationTime" << _calibrationTime;
     fs << "imageSizeWidth" << _imageSize.width;
     fs << "imageSizeHeight" << _imageSize.height;
     fs << "boardSizeWidth" << _boardSize.width;   // do not reload
     fs << "boardSizeHeight" << _boardSize.height; // do not reload
     fs << "boardSquareMM" << _boardSquareMM;      // do not reload
     fs << "numCaptured" << _numCaptured;
     fs << "calibFlags" << _calibFlags;
     fs << "isMirroredH" << _isMirroredH;
     fs << "isMirroredV" << _isMirroredV;
     fs << "calibFixAspectRatio" << (_calibFlags & cv::CALIB_FIX_ASPECT_RATIO);
     fs << "calibFixPrincipalPoint" << (_calibFlags & cv::CALIB_FIX_PRINCIPAL_POINT);
     fs << "calibZeroTangentDist" << (_calibFlags & cv::CALIB_ZERO_TANGENT_DIST);
     fs << "calibRationalModel" << (_calibFlags & cv::CALIB_RATIONAL_MODEL);
     fs << "calibTiltedModel" << (_calibFlags & cv::CALIB_TILTED_MODEL);
     fs << "calibThinPrismModel" << (_calibFlags & cv::CALIB_THIN_PRISM_MODEL);
     fs << "cameraMat" << _cameraMat;
     fs << "distortion" << _distortion;
     fs << "reprojectionError" << _reprojectionError;
     fs << "cameraFovVDeg" << _cameraFovVDeg;
     fs << "cameraFovHDeg" << _cameraFovHDeg;
     fs << "camSizeIndex" << _camSizeIndex;
     fs << "computerInfos" << _computerInfos;
  
     // close file
     fs.release();
     Utils::log("SLProject", "Calib. saved    : %s", fullPathAndFilename.c_str());
     return true;
     // uploadCalibration(fullPathAndFilename);
 }

◆ state()

CVCalibState CVCalibration::state ( ) const

inline

Definition at line 167 of file CVCalibration.h.

167 { return _state; }

◆ stateStr()

string CVCalibration::stateStr ( ) const

inline

Definition at line 176 of file CVCalibration.h.

     {
         switch (_state)
         {
             case CS_uncalibrated: return "CS_uncalibrated";
             case CS_calibrated: return "CS_calibrated";
             case CS_guessed: return "CS_guessed";
             default: return "unknown";
         }
     }

◆ tauX()

float CVCalibration::tauX ( ) const

inline

Definition at line 163 of file CVCalibration.h.

163 { return _distortion.rows >= 13 ? (float)_distortion.at<double>(12, 0) : 0.0f; }

◆ tauY()

float CVCalibration::tauY ( ) const

inline

Definition at line 164 of file CVCalibration.h.

164 { return _distortion.rows >= 14 ? (float)_distortion.at<double>(13, 0) : 0.0f; }

Member Data Documentation

◆ _boardSize

CVSize CVCalibration::_boardSize

private

NO. of inner chessboard corners.

Definition at line 210 of file CVCalibration.h.

◆ _boardSquareMM

float CVCalibration::_boardSquareMM = 20.f

private

Size of chessboard square in mm.

Definition at line 211 of file CVCalibration.h.

◆ _calibFileName

string CVCalibration::_calibFileName

private

name for calibration file

Definition at line 204 of file CVCalibration.h.

◆ _CALIBFILEVERSION

const int CVCalibration::_CALIBFILEVERSION = 6

staticprivate

Global const file format version.

Increase the _CALIBFILEVERSION each time you change the file format.

Definition at line 223 of file CVCalibration.h.

◆ _calibFlags

int CVCalibration::_calibFlags = 0

private

OpenCV calibration flags.

Definition at line 205 of file CVCalibration.h.

◆ _calibrationTime

string CVCalibration::_calibrationTime = "-"

private

Time stamp string of calibration.

Definition at line 219 of file CVCalibration.h.

◆ _cameraFovHDeg

float CVCalibration::_cameraFovHDeg = 0.0f

private

Horizontal field of view in degrees.

Definition at line 203 of file CVCalibration.h.

◆ _cameraFovVDeg

float CVCalibration::_cameraFovVDeg = 0.0f

private

Vertical field of view in degrees.

Definition at line 202 of file CVCalibration.h.

◆ _cameraMat

CVMat CVCalibration::_cameraMat

private

3x3 Matrix for intrinsic camera matrix

Definition at line 193 of file CVCalibration.h.

◆ _cameraMatOrig

CVMat CVCalibration::_cameraMatOrig

private

3x3 Matrix for intrinsic camera matrix (original from loading or calibration estimation)

Definition at line 198 of file CVCalibration.h.

◆ _cameraMatUndistorted

CVMat CVCalibration::_cameraMatUndistorted

private

Camera matrix that defines scene camera and may also be used for reprojection of undistorted image.

Definition at line 218 of file CVCalibration.h.

◆ _camSizeIndex

int CVCalibration::_camSizeIndex = -1

private

The requested camera size index.

Definition at line 214 of file CVCalibration.h.

◆ _camType

CVCameraType CVCalibration::_camType = CVCameraType::FRONTFACING

private

Definition at line 221 of file CVCalibration.h.

◆ _computerInfos

string CVCalibration::_computerInfos

private

Definition at line 220 of file CVCalibration.h.

◆ _distortion

CVMat CVCalibration::_distortion

private

4x1 Matrix for intrinsic distortion

Definition at line 194 of file CVCalibration.h.

◆ _imageSize

CVSize CVCalibration::_imageSize

private

Input image size in pixels (after cropping)

Definition at line 213 of file CVCalibration.h.

◆ _imageSizeOrig

CVSize CVCalibration::_imageSizeOrig

private

original image size (original from loading or calibration estimation)

Definition at line 199 of file CVCalibration.h.

◆ _isMirroredH

bool CVCalibration::_isMirroredH = false

private

Flag if image must be horizontally mirrored.

Definition at line 206 of file CVCalibration.h.

◆ _isMirroredV

bool CVCalibration::_isMirroredV = false

private

Flag if image must be vertically mirrored.

Definition at line 207 of file CVCalibration.h.

◆ _numCaptured

int CVCalibration::_numCaptured = 0

private

NO. of images captured.

Definition at line 209 of file CVCalibration.h.

◆ _reprojectionError

float CVCalibration::_reprojectionError = -1.0f

private

Reprojection error after calibration.

Definition at line 212 of file CVCalibration.h.

◆ _state

CVCalibState CVCalibration::_state = CS_uncalibrated

private

calibration state enumeration

Definition at line 201 of file CVCalibration.h.

◆ _undistortMapX

CVMat CVCalibration::_undistortMapX

private

Undistortion float map in x-direction.

Definition at line 216 of file CVCalibration.h.

◆ _undistortMapY

CVMat CVCalibration::_undistortMapY

private

Undistortion float map in y-direction.

Definition at line 217 of file CVCalibration.h.

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

Public Member Functions

Private Member Functions

Private Attributes

Static Private Attributes

Detailed Description

Constructor & Destructor Documentation

◆ CVCalibration() [1/4]

◆ CVCalibration() [2/4]

◆ CVCalibration() [3/4]

◆ CVCalibration() [4/4]

Member Function Documentation

◆ adaptForNewResolution()

◆ boardSize()

◆ boardSquareM()

◆ boardSquareMM()

◆ buildUndistortionMaps()

◆ calcCameraFovFromUndistortedCameraMat()

◆ calculateUndistortedCameraMat()

◆ calibFileName()

◆ calibFixAspectRatio()

◆ calibFixPrincipalPoint()

◆ calibRationalModel()

◆ calibrationFlags()

◆ calibrationTime()

◆ calibThinPrismModel()

◆ calibTiltedModel()

◆ calibZeroTangentDist()

◆ cameraFovHDeg()

◆ cameraFovVDeg()

◆ cameraMat()

◆ cameraMatUndistorted()

◆ camType()

◆ computerInfos()

◆ createFromGuessedFOV()

◆ cx()

◆ cy()

◆ distortion()

◆ fx()

◆ fy()

◆ imageAspectRatio()

◆ imageSize()

◆ imageSizeOriginal()

◆ isMirroredH()

◆ isMirroredV()

◆ k1()

◆ k2()

◆ k3()

◆ k4()

◆ k5()

◆ k6()

◆ load()

◆ numCapturedImgs()

◆ p1()

◆ p2()

◆ remap()

◆ reprojectionError()

◆ s1()

◆ s2()

◆ s3()

◆ s4()

◆ save()

◆ state()

◆ stateStr()

◆ tauX()

◆ tauY()

Member Data Documentation

◆ _boardSize

◆ _boardSquareMM

◆ _calibFileName

◆ _CALIBFILEVERSION

◆ _calibFlags

◆ _calibrationTime

◆ _cameraFovHDeg

◆ _cameraFovVDeg

◆ _cameraMat

◆ _cameraMatOrig

◆ _cameraMatUndistorted

◆ _camSizeIndex

◆ _camType

◆ _computerInfos