Visual Servoing Platform  version 3.3.0 under development (2020-02-17)
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vpPixelMeterConversion Class Reference
core: Core module » Camera model

#include <visp3/core/vpPixelMeterConversion.h>

Static Public Member Functions

Using ViSP camera parameters
static void convertLine (const vpCameraParameters &cam, const double &rho_p, const double &theta_p, double &rho_m, double &theta_m)
 
static void convertMoment (const vpCameraParameters &cam, unsigned int order, const vpMatrix &moment_pixel, vpMatrix &moment_meter)
 
static void convertPoint (const vpCameraParameters &cam, const double &u, const double &v, double &x, double &y)
 
static void convertPoint (const vpCameraParameters &cam, const vpImagePoint &iP, double &x, double &y)
 
Using OpenCV camera parameters
static void convertLine (const cv::Mat &cameraMatrix, const double &rho_p, const double &theta_p, double &rho_m, double &theta_m)
 
static void convertMoment (const cv::Mat &cameraMatrix, unsigned int order, const vpMatrix &moment_pixel, vpMatrix &moment_meter)
 
static void convertPoint (const cv::Mat &cameraMatrix, const cv::Mat &distCoeffs, const double &u, const double &v, double &x, double &y)
 
static void convertPoint (const cv::Mat &cameraMatrix, const cv::Mat &distCoeffs, const vpImagePoint &iP, double &x, double &y)
 

Detailed Description

Various conversion functions to transform primitives (2D line, moments, 2D point) from pixel to normalized coordinates in meter in the image plane.

Tranformation relies either on ViSP camera parameters implemented in vpCameraParameters or on OpenCV camera parameters that are set from a projection matrix and a distorsion coefficients vector.

Definition at line 71 of file vpPixelMeterConversion.h.

Member Function Documentation

◆ convertLine() [1/2]

void vpPixelMeterConversion::convertLine ( const vpCameraParameters &  cam,
const double &  rho_p,
const double &  theta_p,
double &  rho_m,
double &  theta_m 
)
static

Line parameters conversion from pixel $(\rho_p,\theta_p)$ to normalized coordinates $(\rho_m,\theta_m)$ in meter using ViSP camera parameters. This function doesn't use distorsion coefficients.

Parameters
[in]cam: camera parameters.
[in]rho_p,theta_p: Line parameters expressed in pixels.
[out]rho_m,theta_m: Line parameters expressed in meters in the image plane.

Definition at line 59 of file vpPixelMeterConversion.cpp.

References vpException::divideByZeroError, vpMath::sqr(), and vpERROR_TRACE.

Referenced by vpFeatureBuilder::create().

◆ convertLine() [2/2]

void vpPixelMeterConversion::convertLine ( const cv::Mat &  cameraMatrix,
const double &  rho_p,
const double &  theta_p,
double &  rho_m,
double &  theta_m 
)
static

Line parameters conversion from pixel $(\rho_p,\theta_p)$ to normalized coordinates $(\rho_m,\theta_m)$ in meter using OpenCV camera parameters. This function doesn't use distorsion coefficients.

Parameters
[in]cameraMatrix: Camera Matrix $\begin{bmatrix} f_x & 0 & c_x \\ 0 & f_y & c_y \\ 0 & 0 & 1\end{bmatrix}$
[in]rho_p,theta_p: Line parameters expressed in pixels.
[out]rho_m,theta_m: Line parameters expressed in meters in the image plane.

Definition at line 136 of file vpPixelMeterConversion.cpp.

References vpException::divideByZeroError, vpMath::sqr(), and vpERROR_TRACE.

◆ convertMoment() [1/2]

void vpPixelMeterConversion::convertMoment ( const vpCameraParameters &  cam,
unsigned int  order,
const vpMatrix &  moment_pixel,
vpMatrix &  moment_meter 
)
static

Moments conversion from pixel to normalized coordinates in meter using ViSP camera parameters. This function doesn't use distorsion coefficients.

Parameters
[in]cam: camera parameters.
[in]order: Moment order.
[in]moment_pixel: Moment values in pixels.
[out]moment_meter: Moment values in meters in the image plane.

Definition at line 85 of file vpPixelMeterConversion.cpp.

References vpMath::comb().

Referenced by vpFeatureBuilder::create().

◆ convertMoment() [2/2]

void vpPixelMeterConversion::convertMoment ( const cv::Mat &  cameraMatrix,
unsigned int  order,
const vpMatrix &  moment_pixel,
vpMatrix &  moment_meter 
)
static

Moments conversion from pixel to normalized coordinates in meter using OpenCV camera parameters. This function doesn't use distorsion coefficients.

Parameters
[in]cameraMatrix: Camera Matrix $\begin{bmatrix} f_x & 0 & c_x \\ 0 & f_y & c_y \\ 0 & 0 & 1\end{bmatrix}$
[in]order: Moment order.
[in]moment_pixel: Moment values in pixels.
[out]moment_meter: Moment values in meters in the image plane.

Definition at line 167 of file vpPixelMeterConversion.cpp.

References vpMath::comb().

◆ convertPoint() [1/4]

static void vpPixelMeterConversion::convertPoint ( const vpCameraParameters &  cam,
const double &  u,
const double &  v,
double &  x,
double &  y 
)
inlinestatic

Point coordinates conversion from pixel coordinates $(u,v)$ to normalized coordinates $(x,y)$ in meter using ViSP camera parameters.

The used formula depends on the projection model of the camera. To know the currently used projection model use vpCameraParameter::get_projModel()

Parameters
[in]cam: camera parameters.
[in]u: input coordinate in pixels along image horizontal axis.
[in]v: input coordinate in pixels along image vertical axis.
[out]x: output coordinate in meter along image plane x-axis.
[out]y: output coordinate in meter along image plane y-axis.

$ x = (u-u_0)/p_x $ and $ y = (v-v_0)/p_y $ in the case of perspective projection without distortion.

$ x = (u-u_0)*(1+k_{du}*r^2)/p_x $ and $ y = (v-v_0)*(1+k_{du}*r^2)/p_y $ with $ r^2=((u - u_0)/p_x)^2+((v-v_0)/p_y)^2 $ in the case of perspective projection with distortion.

Examples:
AROgre.cpp, AROgreBasic.cpp, mbot-apriltag-ibvs.cpp, poseVirtualVS.cpp, servoAfma62DhalfCamVelocity.cpp, servoAfma6FourPoints2DCamVelocityLs_cur.cpp, servoAfma6Points2DCamVelocityEyeToHand.cpp, servoBebop2.cpp, servoFlirPtuIBVS.cpp, servoViper650FourPoints2DArtVelocityLs_cur.cpp, servoViper650FourPoints2DCamVelocityLs_cur-SR300.cpp, servoViper650FourPoints2DCamVelocityLs_cur.cpp, servoViper850FourPoints2DArtVelocityLs_cur.cpp, servoViper850FourPoints2DCamVelocityLs_cur.cpp, servoViper850FourPointsKinect.cpp, testAprilTag.cpp, testGenericTracker.cpp, testGenericTrackerDepth.cpp, testKeyPoint-4.cpp, testRobotAfma6Pose.cpp, testRobotViper850Pose.cpp, tutorial-chessboard-pose.cpp, tutorial-flir-ptu-ibvs.cpp, tutorial-matching-keypoint-homography.cpp, tutorial-matching-surf-homography-deprecated.cpp, and tutorial-mb-generic-tracker-rgbd-blender.cpp.

Definition at line 103 of file vpPixelMeterConversion.h.

References vpCameraParameters::perspectiveProjWithDistortion, and vpCameraParameters::perspectiveProjWithoutDistortion.

Referenced by vpCalibration::addPoint(), vpFeatureLuminance::buildFrom(), vpKeyPoint::compute3D(), vpKeyPoint::compute3DForPointsOnCylinders(), vpMbtFaceDepthNormal::computeDesiredFeatures(), vpMbtDistanceKltCylinder::computeInteractionMatrixAndResidu(), vpMbtDistanceKltPoints::computeInteractionMatrixAndResidu(), vpMbtDistanceCircle::computeInteractionMatrixError(), vpPose::computePlanarObjectPoseFromRGBD(), vpFeatureBuilder::create(), vpMomentObject::fromImage(), vpImageSimulator::getImage(), vpMbtDistanceKltCylinder::init(), vpMbTracker::initClick(), vpMbTracker::initFromPoints(), vpKeyPoint::matchPoint(), and vpKinect::warpRGBFrame().

◆ convertPoint() [2/4]

static void vpPixelMeterConversion::convertPoint ( const vpCameraParameters &  cam,
const vpImagePoint &  iP,
double &  x,
double &  y 
)
inlinestatic

Point coordinates conversion from pixel coordinates Coordinates in pixel to normalized coordinates $(x,y)$ in meter using ViSP camera parameters.

The used formula depends on the projection model of the camera. To know the currently used projection model use vpCameraParameter::get_projModel()

Parameters
[in]cam: camera parameters.
[in]iP: input coordinates in pixels.
[out]x: output coordinate in meter along image plane x-axis.
[out]y: output coordinate in meter along image plane y-axis.

Thanks to the pixel coordinates in the frame (u,v), the meter coordinates are given by :

$ x = (u-u_0)/p_x $ and $ y = (v-v_0)/p_y $ in the case of perspective projection without distortion.

$ x = (u-u_0)*(1+k_{du}*r^2)/p_x $ and $ y = (v-v_0)*(1+k_{du}*r^2)/p_y $ with $ r^2=((u - u_0)/p_x)^2+((v-v_0)/p_y)^2 $ in the case of perspective projection with distortion.

Definition at line 140 of file vpPixelMeterConversion.h.

References vpImagePoint::get_u(), vpImagePoint::get_v(), vpCameraParameters::perspectiveProjWithDistortion, vpCameraParameters::perspectiveProjWithoutDistortion, and vpMath::sqr().

◆ convertPoint() [3/4]

void vpPixelMeterConversion::convertPoint ( const cv::Mat &  cameraMatrix,
const cv::Mat &  distCoeffs,
const double &  u,
const double &  v,
double &  x,
double &  y 
)
static

Point coordinates conversion from pixel coordinates $(u,v)$ to normalized coordinates $(x,y)$ in meter using OpenCV camera parameters.

Parameters
[in]cameraMatrix: Camera Matrix $\begin{bmatrix} f_x & 0 & c_x \\ 0 & f_y & c_y \\ 0 & 0 & 1\end{bmatrix}$
[in]distCoeffs: Input vector of distortion coefficients $(k_1, k_2, p_1, p_2[, k_3[, k_4, k_5, k_6 [, s_1, s_2, s_3, s_4[, \tau_x, \tau_y]]]])$ of 4, 5, 8, 12 or 14 elements. If the vector is NULL/empty, the zero distortion coefficients are assumed.
[in]u: input coordinate in pixels along image horizontal axis.
[in]v: input coordinate in pixels along image vertical axis.
[out]x: output coordinate in meter along image plane x-axis.
[out]y: output coordinate in meter along image plane y-axis.

Definition at line 225 of file vpPixelMeterConversion.cpp.

◆ convertPoint() [4/4]

void vpPixelMeterConversion::convertPoint ( const cv::Mat &  cameraMatrix,
const cv::Mat &  distCoeffs,
const vpImagePoint &  iP,
double &  x,
double &  y 
)
static

Point coordinates conversion from pixel coordinates $(u,v)$ to normalized coordinates $(x,y)$ in meter using OpenCV camera parameters.

Parameters
[in]cameraMatrix: Camera Matrix $\begin{bmatrix} f_x & 0 & c_x \\ 0 & f_y & c_y \\ 0 & 0 & 1\end{bmatrix}$
[in]distCoeffs: Input vector of distortion coefficients $(k_1, k_2, p_1, p_2[, k_3[, k_4, k_5, k_6 [, s_1, s_2, s_3, s_4[, \tau_x, \tau_y]]]])$ of 4, 5, 8, 12 or 14 elements. If the vector is NULL/empty, the zero distortion coefficients are assumed.
[in]iP: input coordinates in pixels.
[out]x: output coordinate in meter along image plane x-axis.
[out]y: output coordinate in meter along image plane y-axis.

Definition at line 249 of file vpPixelMeterConversion.cpp.

References vpImagePoint::get_u(), and vpImagePoint::get_v().