#include <visp3/core/vpCameraParameters.h>

Public Types
enum	vpCameraParametersProjType { perspectiveProjWithoutDistortion, perspectiveProjWithDistortion }

Public Member Functions
	vpCameraParameters ()

	vpCameraParameters (const vpCameraParameters &c)

	vpCameraParameters (const double px, const double py, const double u0, const double v0)

	vpCameraParameters (const double px, const double py, const double u0, const double v0, const double kud, const double kdu)

vpCameraParameters &	operator= (const vpCameraParameters &c)

virtual	~vpCameraParameters ()

void	init ()

void	init (const vpCameraParameters &c)

void	initFromCalibrationMatrix (const vpMatrix &_K)

void	initFromFov (const unsigned int &w, const unsigned int &h, const double &hfov, const double &vfov)

void	initPersProjWithoutDistortion (const double px, const double py, const double u0, const double v0)

void	initPersProjWithDistortion (const double px, const double py, const double u0, const double v0, const double kud, const double kdu)

bool	isFovComputed () const

void	computeFov (const unsigned int &w, const unsigned int &h)

double	getHorizontalFovAngle () const

double	getVerticalFovAngle () const

std::vector< vpColVector >	getFovNormals () const

double	get_px () const

double	get_px_inverse () const

double	get_py_inverse () const

double	get_py () const

double	get_u0 () const

double	get_v0 () const

double	get_kud () const

double	get_kdu () const

vpCameraParametersProjType	get_projModel () const

vpMatrix	get_K () const

vpMatrix	get_K_inverse () const

void	printParameters ()

Friends
class	vpMeterPixelConversion

class	vpPixelMeterConversion

VISP_EXPORT std::ostream &	operator<< (std::ostream &os, const vpCameraParameters &cam)

Detailed Description

Generic class defining intrinsic camera parameters.

Let us define the pinhole camera model implemented in ViSP. In this model, a scene view is formed by projecting 3D points into the image plane using a perspective transformation.

$\left[ \begin{array}{c} u \\ v \\ 1 \end{array}\right] = \left[ \begin{array}{ccc} u_0 & 0 & p_x \\ 0 & v_0 & p_y \\ 0 & 0 & 1 \end{array}\right] \left[ \begin{array}{c} X_c \\ Y_c \\ Z_c \end{array}\right]$

where:

are the coordinates of a 3D point in the camera frame
are the coordinates in pixels of the projected 3D point
is a principal point that is usually near the image center
are the focal lengths expressed in pixel units.

When $Z_c \neq 0$ , the previous equation si equivalent to the following:

$\begin{array}{lcl} x &=& X_c / Z_c \\ y &=& Y_c / Z_c \\ u &=& u_0 + x \; p_x \\ v &=& v_0 + y \; p_y \end{array}$

Real lenses usually have some radial distortion. So, the above model is extended as:

$\begin{array}{lcl} x &=& X_c / Z_c \\ y &=& Y_c / Z_c \\ x^{'} &=& x (1 + k_{ud} r^2) \\ y^{'} &=& y (1 + k_{ud} r^2) \\ r^2 &=& x^2 + y^2 \\ u &=& u_0 + x^{'} \; p_x \\ v &=& v_0 + y^{'} \; p_y \end{array}$

where $k_{ud}$ is the first order radial distorsion. Higher order distorsion coefficients are not considered in ViSP.

Now in ViSP we consider also the inverse transformation, where from pixel coordinates we want to compute their normalized coordinates in the image plane. Previous equations could be written like:

$\begin{array}{lcl} x &=& (u - u_0) / p_x \\ y &=& (v - v_0) / p_y \end{array}$

Considering radial distortion, the above model is extended as:

$\begin{array}{lcl} (u-u_0)^{'} &=& (u-u_0) (1 + k_{du} r^2) \\ (v-v_0)^{'} &=& (v-v_0) (1 + k_{du} r^2) \\ r^2 &=& ((u-u_0)/p_x)^2 + ((v-v_0)/p_y)^2 \\ x &=& (u - u_0)^{'} / p_x \\ y &=& (v - v_0)^{'} / p_y \end{array}$

Finally, in ViSP the main intrinsic camera parameters are $(p_x, p_y)$ the ratio between the focal length and the size of a pixel, and $(u_0, v_0)$ the coordinates of the principal point in pixel. The lens distortion can also be considered by two additional parameters $(k_{ud}, k_{du})$ .

Note: Tutorial: Camera calibration shows how to calibrate a camera to estimate the parameters corresponding to the model implemented in this class.; Note also that Tutorial: Bridge over OpenCV gives the correspondance between ViSP and OpenCV camera modelization.; The conversion from pixel coordinates in the normalized space is implemented in vpPixelMeterConversion, whereas the conversion from normalized coordinates into pixel is implemented in vpMeterPixelConversion.

From a practical point of view, two kinds of camera modelisation are implemented in this class:

1. Camera parameters for a perspective projection without distortion model

In this modelisation, only $u_0,v_0,p_x,p_y$ parameters are considered.

Initialization of such a model can be done using:

initPersProjWithoutDistortion() that allows to set parameters;
initFromFov() that computes the parameters from an image size and a camera field of view.

2. Camera parameters for a perspective projection with distortion model

In this modelisation, all the parameters $u_0,v_0,p_x,p_y,k_{ud},k_{du}$ are considered. Initialization of such a model can be done using:

initPersProjWithDistortion() that allows to set $u_0,v_0,p_x,p_y,k_{ud},k_{du}$ parameters;

The selection of the camera model (without or with distorsion) is done during vpCameraParameters initialisation.

Here an example of camera initialisation, for a model without distortion. A complete example is given in initPersProjWithoutDistortion().

double px = 600;
double py = 600;
double u0 = 320;
double v0 = 240;
// Create a camera parameter container
vpCameraParameters cam;
// Camera initialization with a perspective projection without distortion model
cam.initPersProjWithoutDistortion(px,py,u0,v0);
// It is also possible to print the current camera parameters
std::cout << cam << std::endl;

Here an example of camera initialisation, for a model with distortion. A complete example is given in initPersProjWithDistortion().

double px = 600;
double py = 600;
double u0 = 320;
double v0 = 240;
double kud = -0.19;
double kdu = 0.20;
// Create a camera parameter container
vpCameraParameters cam;
// Camera initialization with a perspective projection without distortion model
cam.initPersProjWithDistortion(px,py,u0,v0,kud,kdu);

The code below shows how to know the currently used projection model:

vpCameraParameters cam;
...
vpCameraParameters::vpCameraParametersProjType projModel;
projModel = cam.get_projModel(); // Get the projection model type

An XML parser for camera parameters is also provided in vpXmlParserCamera.

Examples:: AROgre.cpp, AROgreBasic.cpp, HelloWorldOgre.cpp, HelloWorldOgreAdvanced.cpp, manGeometricFeatures.cpp, manServo4PointsDisplay.cpp, manSimu4Dots.cpp, manSimu4Points.cpp, mbtEdgeKltTracking.cpp, mbtEdgeTracking.cpp, mbtKltTracking.cpp, photometricVisualServoing.cpp, poseVirtualVS.cpp, servoAfma4Point2DArtVelocity.cpp, servoAfma4Point2DCamVelocity.cpp, servoAfma4Point2DCamVelocityKalman.cpp, servoAfma62DhalfCamVelocity.cpp, servoAfma6Cylinder2DCamVelocity.cpp, servoAfma6Cylinder2DCamVelocitySecondaryTask.cpp, servoAfma6Ellipse2DCamVelocity.cpp, servoAfma6FourPoints2DArtVelocity.cpp, servoAfma6FourPoints2DCamVelocityInteractionCurrent.cpp, servoAfma6FourPoints2DCamVelocityInteractionDesired.cpp, servoAfma6Line2DCamVelocity.cpp, servoAfma6Point2DArtVelocity.cpp, servoAfma6Point2DCamVelocity.cpp, servoAfma6Points2DCamVelocityEyeToHand.cpp, servoAfma6Segment2DCamVelocity.cpp, servoAfma6SquareLines2DCamVelocity.cpp, servoAfma6TwoLines2DCamVelocity.cpp, servoBiclopsPoint2DArtVelocity.cpp, servoMomentImage.cpp, servoMomentPoints.cpp, servoMomentPolygon.cpp, servoPioneerPanSegment3D.cpp, servoPioneerPoint2DDepth.cpp, servoPioneerPoint2DDepthWithoutVpServo.cpp, servoPtu46Point2DArtVelocity.cpp, servoSimu4Points.cpp, servoSimuAfma6FourPoints2DCamVelocity.cpp, servoSimuCircle2DCamVelocityDisplay.cpp, servoSimuCylinder.cpp, servoSimuCylinder2DCamVelocityDisplay.cpp, servoSimuCylinder2DCamVelocityDisplaySecondaryTask.cpp, servoSimuFourPoints2DCamVelocityDisplay.cpp, servoSimuFourPoints2DPolarCamVelocityDisplay.cpp, servoSimuLine2DCamVelocityDisplay.cpp, servoSimuSphere.cpp, servoSimuSquareLine2DCamVelocityDisplay.cpp, servoSimuViper850FourPoints2DCamVelocity.cpp, servoViper650FourPoints2DArtVelocityInteractionCurrent.cpp, servoViper650FourPoints2DCamVelocityInteractionCurrent.cpp, servoViper650Point2DCamVelocity.cpp, servoViper850FourPoints2DArtVelocityInteractionCurrent.cpp, servoViper850FourPoints2DArtVelocityInteractionDesired.cpp, servoViper850FourPoints2DCamVelocityInteractionCurrent.cpp, servoViper850FourPointsKinect.cpp, servoViper850Point2DArtVelocity-jointAvoidance-basic.cpp, servoViper850Point2DArtVelocity-jointAvoidance-gpa.cpp, servoViper850Point2DArtVelocity-jointAvoidance-large.cpp, servoViper850Point2DArtVelocity.cpp, servoViper850Point2DCamVelocity.cpp, servoViper850Point2DCamVelocityKalman.cpp, simulateCircle2DCamVelocity.cpp, simulateFourPoints2DCartesianCamVelocity.cpp, simulateFourPoints2DPolarCamVelocity.cpp, testAfma6.cpp, testFeatureSegment.cpp, testKeyPoint-2.cpp, testKeyPoint-4.cpp, testRobotAfma6.cpp, testRobotAfma6Pose.cpp, testRobotViper850.cpp, testRobotViper850Pose.cpp, testTrackDot.cpp, testUndistortImage.cpp, testViper850.cpp, trackMeLine.cpp, tutorial-bridge-opencv.cpp, tutorial-detection-object-mbt.cpp, tutorial-detection-object-mbt2.cpp, tutorial-homography-from-points.cpp, tutorial-ibvs-4pts-display.cpp, tutorial-ibvs-4pts-image-tracking.cpp, tutorial-ibvs-4pts-ogre-tracking.cpp, tutorial-ibvs-4pts-ogre.cpp, tutorial-ibvs-4pts-wireframe-camera.cpp, tutorial-ibvs-4pts-wireframe-robot-afma6.cpp, tutorial-ibvs-4pts-wireframe-robot-viper.cpp, tutorial-image-simulator.cpp, tutorial-matching-keypoint-homography.cpp, tutorial-matching-surf-homography-deprecated.cpp, tutorial-mb-edge-tracker.cpp, tutorial-mb-hybrid-tracker.cpp, tutorial-mb-klt-tracker.cpp, tutorial-mb-tracker-full.cpp, tutorial-mb-tracker.cpp, tutorial-pose-from-points-image.cpp, tutorial-pose-from-points-tracking.cpp, tutorial-undistort.cpp, and wireframeSimulator.cpp.

Definition at line 218 of file vpCameraParameters.h.

Member Enumeration Documentation

enum vpCameraParameters::vpCameraParametersProjType

Enumerator
perspectiveProjWithoutDistortion	Perspective projection without distortion model.
perspectiveProjWithDistortion	Perspective projection with distortion model.

Definition at line 223 of file vpCameraParameters.h.

Constructor & Destructor Documentation

vpCameraParameters::vpCameraParameters ( )

Default constructor. By default, a perspective projection without distortion model is set.

See also: init()

Definition at line 73 of file vpCameraParameters.cpp.

References init().

vpCameraParameters::vpCameraParameters ( const vpCameraParameters & c )

Copy constructor

Definition at line 89 of file vpCameraParameters.cpp.

References init().

vpCameraParameters::vpCameraParameters	(	const double	cam_px,
		const double	cam_py,
		const double	cam_u0,
		const double	cam_v0
	)

Constructor for perspective projection without distortion model

Parameters

cam_px,cam_py	: pixel size
cam_u0,cam_v0	: principal points

Definition at line 109 of file vpCameraParameters.cpp.

References initPersProjWithoutDistortion().

vpCameraParameters::vpCameraParameters	(	const double	cam_px,
		const double	cam_py,
		const double	cam_u0,
		const double	cam_v0,
		const double	cam_kud,
		const double	cam_kdu
	)

Constructor for perspective projection with distortion model

Parameters

cam_px,cam_py	: pixel size
cam_u0,cam_v0	: principal points
cam_kud	: undistorted to distorted radial distortion
cam_kdu	: distorted to undistorted radial distortion

Definition at line 132 of file vpCameraParameters.cpp.

References initPersProjWithDistortion().

vpCameraParameters::~vpCameraParameters ( )

virtual

destructor

nothing much to destroy...

Definition at line 309 of file vpCameraParameters.cpp.

Member Function Documentation

void vpCameraParameters::computeFov	(	const unsigned int &	w,
		const unsigned int &	h
	)

Compute angles and normals of the FOV.

Parameters

w	: Width of the image
h	: Height of the image.

Definition at line 432 of file vpCameraParameters.cpp.

References vpColVector::normalize().

Referenced by vpMbtDistanceLine::display(), vpMbKltTracker::display(), vpMbEdgeTracker::init(), initFromFov(), vpMbtDistanceLine::initMovingEdge(), vpMbtPolygon::isVisible(), vpMbEdgeKltTracker::postTracking(), vpMbKltTracker::reinit(), vpMbEdgeKltTracker::setPose(), vpMbKltTracker::setPose(), and vpMbtDistanceLine::updateMovingEdge().

vpMatrix vpCameraParameters::get_K ( ) const

Return the camera matrix $K$ given by:

$K = \left[\begin{array}{ccc} p_x & 0 & u_0 \\ 0 & p_y & v_0 \\ 0 & 0 & 1 \end{array} \right]$

See also: get_K_inverse()

Definition at line 494 of file vpCameraParameters.cpp.

Referenced by vpMbEdgeTracker::downScale(), vpPose::poseFromRectangle(), vpHomography::project(), vpMbKltTracker::setPose(), and vpMbEdgeTracker::upScale().

vpMatrix vpCameraParameters::get_K_inverse ( ) const

Return the inverted camera matrix $K^{-1}$ given by:

$K^{-1} = \left[\begin{array}{ccc} 1/p_x & 0 & -u_0/p_x \\ 0 & 1/p_y & -v_0/p_y \\ 0 & 0 & 1 \end{array} \right]$

See also: get_K()

Definition at line 517 of file vpCameraParameters.cpp.

Referenced by vpHomography::project(), and vpMbKltTracker::setPose().

double vpCameraParameters::get_kdu ( ) const

inline

Definition at line 307 of file vpCameraParameters.h.

Referenced by vpCalibration::computeStdDeviation_dist().

double vpCameraParameters::get_kud ( ) const

inline

Examples:: tutorial-bridge-opencv.cpp.

Definition at line 306 of file vpCameraParameters.h.

Referenced by vpCalibration::computeStdDeviation_dist(), vpCalibration::displayGrid(), and vpImageTools::undistort().

vpCameraParametersProjType vpCameraParameters::get_projModel ( ) const

inline

Definition at line 309 of file vpCameraParameters.h.

Referenced by vpXmlParserCamera::save().

double vpCameraParameters::get_px ( ) const

inline

Examples:: servoPioneerPanSegment3D.cpp, servoPioneerPoint2DDepth.cpp, servoPioneerPoint2DDepthWithoutVpServo.cpp, testKeyPoint-2.cpp, tutorial-bridge-opencv.cpp, tutorial-detection-object-mbt2.cpp, tutorial-matching-keypoint-homography.cpp, and tutorial-matching-surf-homography-deprecated.cpp.

Definition at line 300 of file vpCameraParameters.h.

Referenced by vpFeatureLuminance::buildFrom(), vpMbtDistanceLine::computeInteractionMatrixError(), vpMbtDistanceCylinder::computeInteractionMatrixError(), vpCircle::computeIntersectionPoint(), vpKeyPoint::computePose(), vpCalibration::computeStdDeviation(), vpCalibration::computeStdDeviation_dist(), vpMbEdgeKltTracker::computeVVS(), vpMbKltTracker::computeVVS(), vpMbEdgeTracker::computeVVS(), vpMeterPixelConversion::convertEllipse(), vpCalibration::displayGrid(), vpMomentObject::fromImage(), vpSimulatorAfma6::initDisplay(), vpSimulatorViper850::initDisplay(), vpMbXmlParser::read_camera(), vpMbtEdgeKltXmlParser::readMainClass(), vpMbtXmlParser::readMainClass(), vpMbtKltXmlParser::readMainClass(), vpMbXmlParser::readMainClass(), vpSimulatorAfma6::setCameraParameters(), vpSimulatorViper850::setCameraParameters(), vpSimulator::setExternalCameraParameters(), vpWireFrameSimulator::setExternalCameraParameters(), vpSimulator::setInternalCameraParameters(), vpWireFrameSimulator::setInternalCameraParameters(), vpImageTools::undistort(), and vpAROgre::updateCameraProjection().

double vpCameraParameters::get_px_inverse ( ) const

inline

Definition at line 301 of file vpCameraParameters.h.

double vpCameraParameters::get_py ( ) const

inline

Examples:: servoPioneerPanSegment3D.cpp, servoPioneerPoint2DDepth.cpp, servoPioneerPoint2DDepthWithoutVpServo.cpp, testKeyPoint-2.cpp, tutorial-bridge-opencv.cpp, and tutorial-detection-object-mbt2.cpp.

Definition at line 303 of file vpCameraParameters.h.

Referenced by vpFeatureLuminance::buildFrom(), vpMbtDistanceLine::computeInteractionMatrixError(), vpMbtDistanceCylinder::computeInteractionMatrixError(), vpCircle::computeIntersectionPoint(), vpKeyPoint::computePose(), vpCalibration::computeStdDeviation(), vpCalibration::computeStdDeviation_dist(), vpMeterPixelConversion::convertEllipse(), vpCalibration::displayGrid(), vpMomentObject::fromImage(), vpSimulatorAfma6::initDisplay(), vpSimulatorViper850::initDisplay(), vpMbXmlParser::read_camera(), vpMbtEdgeKltXmlParser::readMainClass(), vpMbtXmlParser::readMainClass(), vpMbtKltXmlParser::readMainClass(), vpMbXmlParser::readMainClass(), vpSimulatorAfma6::setCameraParameters(), vpSimulatorViper850::setCameraParameters(), vpSimulator::setExternalCameraParameters(), vpWireFrameSimulator::setExternalCameraParameters(), vpSimulator::setInternalCameraParameters(), vpWireFrameSimulator::setInternalCameraParameters(), vpImageTools::undistort(), and vpAROgre::updateCameraProjection().

double vpCameraParameters::get_py_inverse ( ) const

inline

Definition at line 302 of file vpCameraParameters.h.

double vpCameraParameters::get_u0 ( ) const

inline

double vpCameraParameters::get_v0 ( ) const

inline

std::vector<vpColVector> vpCameraParameters::getFovNormals ( ) const

inline

Get the list of the normals corresponding to planes describing the field of view.

vector[0] : Left Normal.
vector[1] : Right Normal.
vector[2] : Up Normal.
vector[3] : Down Normal.

See also: computeFov()

Returns: List of the normals.

Definition at line 295 of file vpCameraParameters.h.

References vpTRACE.

Referenced by vpPolygon3D::computePolygonClipped().

double vpCameraParameters::getHorizontalFovAngle ( ) const

inline

Get the horizontal angle in radian of the field of view.

Returns: FOV horizontal angle computed with px and width.

See also: computeFov(), getVerticalFovAngle()

Definition at line 267 of file vpCameraParameters.h.

References vpTRACE.

double vpCameraParameters::getVerticalFovAngle ( ) const

inline

Get the vertical angle in radian of the field of view.

Returns: FOV vertical angle computed with py and height.

See also: computeFov(), getHorizontalFovAngle()

Definition at line 279 of file vpCameraParameters.h.

References vpTRACE.

void vpCameraParameters::init ( )

basic initialization with the default parameters

Examples:: AROgre.cpp, and AROgreBasic.cpp.

Definition at line 151 of file vpCameraParameters.cpp.

References vpException::divideByZeroError, and vpERROR_TRACE.

Referenced by vpCameraParameters().

void vpCameraParameters::init ( const vpCameraParameters & c )

initialization from another vpCameraParameters object

Definition at line 317 of file vpCameraParameters.cpp.

void vpCameraParameters::initFromCalibrationMatrix ( const vpMatrix & _K )

initialise the camera from a calibration matrix. Using a calibration matrix leads to a camera without distortion

The K matrix in parameters must be like:

$K = \left(\begin{array}{ccc} p_x & 0 & u_0 \\ 0 & p_y & v_0 \\ 0 & 0 & 1 \end{array} \right)$

Parameters

_K	: the 3by3 calibration matrix

Definition at line 338 of file vpCameraParameters.cpp.

References vpException::badValue, vpException::dimensionError, vpArray2D< Type >::getCols(), vpArray2D< Type >::getRows(), and initPersProjWithoutDistortion().

Referenced by vpMbEdgeTracker::downScale(), and vpMbEdgeTracker::upScale().

void vpCameraParameters::initFromFov	(	const unsigned int &	w,
		const unsigned int &	h,
		const double &	hfov,
		const double &	vfov
	)

Initialize the camera model without distorsion from the image dimension and the camera field of view.

Parameters

w	: Image width.
h	: Image height.
hfov	: Camera horizontal field of view angle expressed in radians.
vfov	: Camera vertical field of view angle expressed in radians.

The following sample code shows how to use this function:

#include <visp3/core/vpCameraParameters.h>
#include <visp3/core/vpImage.h>
int main()
{
  vpImage<unsigned char> I(480, 640);
  vpCameraParameters cam;
  double hfov = vpMath::rad(56);
  double vfov = vpMath::rad(43);
  cam.initFromFov(I.getWidth(), I.getHeight(), hfov, vfov);
  std::cout << cam << std::endl;
  std::cout << "Field of view (horizontal: " << vpMath::deg(cam.getHorizontalFovAngle())
            << " and vertical: " << vpMath::deg(cam.getVerticalFovAngle()) << " degrees)" << std::endl;
}

It produces the following output:

Camera parameters for perspective projection without distortion:
  px = 601.832   py = 609.275
  u0 = 320   v0 = 240
Field of view (horizontal: 56 and vertical: 43 degrees)

Definition at line 384 of file vpCameraParameters.cpp.

References computeFov(), and perspectiveProjWithoutDistortion.

void vpCameraParameters::initPersProjWithDistortion	(	const double	cam_px,
		const double	cam_py,
		const double	cam_u0,
		const double	cam_v0,
		const double	cam_kud,
		const double	cam_kdu
	)

Initialization with specific parameters using perpective projection with distortion model.

Parameters

cam_px,cam_py	: the ratio between the focal length and the size of a pixel.
cam_u0,cam_v0	: principal points coordinates in pixels.
cam_kud	: undistorted to distorted radial distortion.
cam_kdu	: distorted to undistorted radial distortion.

The following sample code shows how to use this function:

#include <visp3/core/vpCameraParameters.h>
#include <visp3/core/vpImage.h>
int main()
{
  vpImage<unsigned char> I(480, 640);
  double u0 = I.getWidth()  / 2.;
  double v0 = I.getHeight() / 2.;
  double px = 600;
  double py = 600;
  double kud = -0.19;
  double kdu = 0.20;
  vpCameraParameters cam;
  cam.initPersProjWithDistortion(px, py, u0, v0, kud, kdu);
  cam.computeFov(I.getWidth(), I.getHeight());
  std::cout << cam << std::endl;
  std::cout << "Field of view (horizontal: " << vpMath::deg(cam.getHorizontalFovAngle())
            << " and vertical: " << vpMath::deg(cam.getVerticalFovAngle()) << " degrees)" << std::endl;
}

It produces the following output:

Camera parameters for perspective projection with distortion:
  px = 600   py = 600
  u0 = 320   v0 = 240
  kud = -0.19
  kdu = 0.2
Field of view (horizontal: 56.14497387 and vertical: 43.60281897 degrees)   

Examples:: testUndistortImage.cpp, and tutorial-undistort.cpp.

Definition at line 275 of file vpCameraParameters.cpp.

References vpException::divideByZeroError, perspectiveProjWithDistortion, and vpERROR_TRACE.

Referenced by vpViper850::getCameraParameters(), vpViper650::getCameraParameters(), vpAfma6::getCameraParameters(), vpKinect::start(), and vpCameraParameters().

void vpCameraParameters::initPersProjWithoutDistortion	(	const double	cam_px,
		const double	cam_py,
		const double	cam_u0,
		const double	cam_v0
	)

Initialization with specific parameters using perpective projection without distortion model.

Parameters

cam_px,cam_py	: the ratio between the focal length and the size of a pixel.
cam_u0,cam_v0	: principal point coordinates in pixels.

The following sample code shows how to use this function:

#include <visp3/core/vpCameraParameters.h>
#include <visp3/core/vpImage.h>
int main()
{
  vpImage<unsigned char> I(480, 640);
  double u0 = I.getWidth()  / 2.;
  double v0 = I.getHeight() / 2.;
  double px = 600;
  double py = 600;
  vpCameraParameters cam;
  cam.initPersProjWithoutDistortion(px, py, u0, v0);
  cam.computeFov(I.getWidth(), I.getHeight());
  std::cout << cam << std::endl;
  std::cout << "Field of view (horizontal: " << vpMath::deg(cam.getHorizontalFovAngle())
            << " and vertical: " << vpMath::deg(cam.getVerticalFovAngle()) << " degrees)" << std::endl;
}

It produces the following output:

Camera parameters for perspective projection without distortion:
  px = 600   py = 600
  u0 = 320   v0 = 240
Field of view (horizontal: 56.145 and vertical: 43.6028 degrees)