vpCalibration.cpp

/****************************************************************************
 *
 * ViSP, open source Visual Servoing Platform software.
 * Copyright (C) 2005 - 2019 by Inria. All rights reserved.
 *
 * This software is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 * See the file LICENSE.txt at the root directory of this source
 * distribution for additional information about the GNU GPL.
 *
 * For using ViSP with software that can not be combined with the GNU
 * GPL, please contact Inria about acquiring a ViSP Professional
 * Edition License.
 *
 * See http://visp.inria.fr for more information.
 *
 * This software was developed at:
 * Inria Rennes - Bretagne Atlantique
 * Campus Universitaire de Beaulieu
 * 35042 Rennes Cedex
 * France
 *
 * If you have questions regarding the use of this file, please contact
 * Inria at visp@inria.fr
 *
 * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
 * WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 *
 * Description:
 * Camera calibration.
 *
 * Authors:
 * Eric Marchand
 * Francois Chaumette
 * Anthony Saunier
 *
 *****************************************************************************/

#include <visp3/core/vpDebug.h>
#include <visp3/core/vpPixelMeterConversion.h>
#include <visp3/vision/vpCalibration.h>
#include <visp3/vision/vpPose.h>

double vpCalibration::threshold = 1e-10f;
unsigned int vpCalibration::nbIterMax = 4000;
double vpCalibration::gain = 0.25;
int vpCalibration::init()
{
  npt = 0;

  residual = residual_dist = 1000.;

  LoX.clear();
  LoY.clear();
  LoZ.clear();
  Lip.clear();

  return 0;
}

vpCalibration::vpCalibration()
  : cMo(), cMo_dist(), cam(), cam_dist(), rMe(), eMc(), eMc_dist(), npt(0), LoX(), LoY(), LoZ(), Lip(), residual(1000.),
    residual_dist(1000.)
{
  init();
}
vpCalibration::vpCalibration(const vpCalibration &c)
  : cMo(), cMo_dist(), cam(), cam_dist(), rMe(), eMc(), eMc_dist(), npt(0), LoX(), LoY(), LoZ(), Lip(), residual(1000.),
    residual_dist(1000.)
{
  (*this) = c;
}

vpCalibration::~vpCalibration() { clearPoint(); }

vpCalibration &vpCalibration::operator=(const vpCalibration &twinCalibration)
{
  npt = twinCalibration.npt;
  LoX = twinCalibration.LoX;
  LoY = twinCalibration.LoY;
  LoZ = twinCalibration.LoZ;
  Lip = twinCalibration.Lip;

  residual = twinCalibration.residual;
  cMo = twinCalibration.cMo;
  residual_dist = twinCalibration.residual_dist;
  cMo_dist = twinCalibration.cMo_dist;

  cam = twinCalibration.cam;
  cam_dist = twinCalibration.cam_dist;

  rMe = twinCalibration.rMe;

  eMc = twinCalibration.eMc;
  eMc_dist = twinCalibration.eMc_dist;

  return (*this);
}

int vpCalibration::clearPoint()
{
  LoX.clear();
  LoY.clear();
  LoZ.clear();
  Lip.clear();
  npt = 0;

  return 0;
}

int vpCalibration::addPoint(double X, double Y, double Z, vpImagePoint &ip)
{
  LoX.push_back(X);
  LoY.push_back(Y);
  LoZ.push_back(Z);

  Lip.push_back(ip);

  npt++;

  return 0;
}

void vpCalibration::computePose(const vpCameraParameters &camera, vpHomogeneousMatrix &cMo_est)
{
  // The vpPose class mainly contents a list of vpPoint (that is (X,Y,Z, x, y)
  // )
  vpPose pose;
  //  the list of point is cleared (if that's not done before)
  pose.clearPoint();
  // we set the 3D points coordinates (in meter !) in the object/world frame
  std::list<double>::const_iterator it_LoX = LoX.begin();
  std::list<double>::const_iterator it_LoY = LoY.begin();
  std::list<double>::const_iterator it_LoZ = LoZ.begin();
  std::list<vpImagePoint>::const_iterator it_Lip = Lip.begin();

  for (unsigned int i = 0; i < npt; i++) {
    vpPoint P(*it_LoX, *it_LoY, *it_LoZ);
    double x = 0, y = 0;
    vpPixelMeterConversion::convertPoint(camera, *it_Lip, x, y);
    P.set_x(x);
    P.set_y(y);

    pose.addPoint(P);
    ++it_LoX;
    ++it_LoY;
    ++it_LoZ;
    ++it_Lip;
  }
  vpHomogeneousMatrix cMo_dementhon; // computed pose with dementhon
  vpHomogeneousMatrix cMo_lagrange;  // computed pose with dementhon

  // compute the initial pose using Lagrange method followed by a non linear
  // minimisation method
  // Pose by Lagrange it provides an initialization of the pose
  pose.computePose(vpPose::LAGRANGE, cMo_lagrange);
  double residual_lagrange = pose.computeResidual(cMo_lagrange);

  // compute the initial pose using Dementhon method followed by a non linear
  // minimisation method
  // Pose by Dementhon it provides an initialization of the pose
  pose.computePose(vpPose::DEMENTHON, cMo_dementhon);
  double residual_dementhon = pose.computeResidual(cMo_dementhon);

  // we keep the better initialization
  if (residual_lagrange < residual_dementhon)
    cMo_est = cMo_lagrange;
  else
    cMo_est = cMo_dementhon;

  // the pose is now refined using the virtual visual servoing approach
  // Warning: cMo needs to be initialized otherwise it may diverge
  pose.computePose(vpPose::VIRTUAL_VS, cMo_est);
}

double vpCalibration::computeStdDeviation(const vpHomogeneousMatrix &cMo_est, const vpCameraParameters &camera)
{
  double residual_ = 0;

  std::list<double>::const_iterator it_LoX = LoX.begin();
  std::list<double>::const_iterator it_LoY = LoY.begin();
  std::list<double>::const_iterator it_LoZ = LoZ.begin();
  std::list<vpImagePoint>::const_iterator it_Lip = Lip.begin();

  double u0 = camera.get_u0();
  double v0 = camera.get_v0();
  double px = camera.get_px();
  double py = camera.get_py();
  vpImagePoint ip;

  for (unsigned int i = 0; i < npt; i++) {
    double oX = *it_LoX;
    double oY = *it_LoY;
    double oZ = *it_LoZ;

    double cX = oX * cMo_est[0][0] + oY * cMo_est[0][1] + oZ * cMo_est[0][2] + cMo_est[0][3];
    double cY = oX * cMo_est[1][0] + oY * cMo_est[1][1] + oZ * cMo_est[1][2] + cMo_est[1][3];
    double cZ = oX * cMo_est[2][0] + oY * cMo_est[2][1] + oZ * cMo_est[2][2] + cMo_est[2][3];

    double x = cX / cZ;
    double y = cY / cZ;

    ip = *it_Lip;
    double u = ip.get_u();
    double v = ip.get_v();

    double xp = u0 + x * px;
    double yp = v0 + y * py;

    residual_ += (vpMath::sqr(xp - u) + vpMath::sqr(yp - v));

    ++it_LoX;
    ++it_LoY;
    ++it_LoZ;
    ++it_Lip;
  }
  this->residual = residual_;
  return sqrt(residual_ / npt);
}
double vpCalibration::computeStdDeviation_dist(const vpHomogeneousMatrix &cMo_est, const vpCameraParameters &camera)
{
  double residual_ = 0;

  std::list<double>::const_iterator it_LoX = LoX.begin();
  std::list<double>::const_iterator it_LoY = LoY.begin();
  std::list<double>::const_iterator it_LoZ = LoZ.begin();
  std::list<vpImagePoint>::const_iterator it_Lip = Lip.begin();

  double u0 = camera.get_u0();
  double v0 = camera.get_v0();
  double px = camera.get_px();
  double py = camera.get_py();
  double kud = camera.get_kud();
  double kdu = camera.get_kdu();

  double inv_px = 1 / px;
  double inv_py = 1 / px;
  vpImagePoint ip;

  for (unsigned int i = 0; i < npt; i++) {
    double oX = *it_LoX;
    double oY = *it_LoY;
    double oZ = *it_LoZ;

    double cX = oX * cMo_est[0][0] + oY * cMo_est[0][1] + oZ * cMo_est[0][2] + cMo_est[0][3];
    double cY = oX * cMo_est[1][0] + oY * cMo_est[1][1] + oZ * cMo_est[1][2] + cMo_est[1][3];
    double cZ = oX * cMo_est[2][0] + oY * cMo_est[2][1] + oZ * cMo_est[2][2] + cMo_est[2][3];

    double x = cX / cZ;
    double y = cY / cZ;

    ip = *it_Lip;
    double u = ip.get_u();
    double v = ip.get_v();

    double r2ud = 1 + kud * (vpMath::sqr(x) + vpMath::sqr(y));

    double xp = u0 + x * px * r2ud;
    double yp = v0 + y * py * r2ud;

    residual_ += (vpMath::sqr(xp - u) + vpMath::sqr(yp - v));

    double r2du = (vpMath::sqr((u - u0) * inv_px) + vpMath::sqr((v - v0) * inv_py));

    xp = u0 + x * px - kdu * (u - u0) * r2du;
    yp = v0 + y * py - kdu * (v - v0) * r2du;

    residual_ += (vpMath::sqr(xp - u) + vpMath::sqr(yp - v));
    ++it_LoX;
    ++it_LoY;
    ++it_LoZ;
    ++it_Lip;
  }
  residual_ /= 2;

  this->residual_dist = residual_;
  return sqrt(residual_ / npt);
}

void vpCalibration::computeStdDeviation(double &deviation, double &deviation_dist)
{
  deviation = computeStdDeviation(cMo, cam);
  deviation_dist = computeStdDeviation_dist(cMo_dist, cam_dist);
}

int vpCalibration::computeCalibration(vpCalibrationMethodType method, vpHomogeneousMatrix &cMo_est,
                                      vpCameraParameters &cam_est, bool verbose)
{
  try {
    computePose(cam_est, cMo_est);
    switch (method) {
    case CALIB_LAGRANGE:
    case CALIB_LAGRANGE_VIRTUAL_VS: {
      calibLagrange(cam_est, cMo_est);
    } break;
    case CALIB_VIRTUAL_VS:
    case CALIB_VIRTUAL_VS_DIST:
    case CALIB_LAGRANGE_VIRTUAL_VS_DIST:
    default:
      break;
    }

    switch (method) {
    case CALIB_VIRTUAL_VS:
    case CALIB_VIRTUAL_VS_DIST:
    case CALIB_LAGRANGE_VIRTUAL_VS:
    case CALIB_LAGRANGE_VIRTUAL_VS_DIST: {
      if (verbose) {
        std::cout << "start calibration without distortion" << std::endl;
      }
      calibVVS(cam_est, cMo_est, verbose);
    } break;
    case CALIB_LAGRANGE:
    default:
      break;
    }
    this->cMo = cMo_est;
    this->cMo_dist = cMo_est;

    // Print camera parameters
    if (verbose) {
      //       std::cout << "Camera parameters without distortion :" <<
      //       std::endl;
      cam_est.printParameters();
    }

    this->cam = cam_est;

    switch (method) {
    case CALIB_VIRTUAL_VS_DIST:
    case CALIB_LAGRANGE_VIRTUAL_VS_DIST: {
      if (verbose) {
        std::cout << "start calibration with distortion" << std::endl;
      }
      calibVVSWithDistortion(cam_est, cMo_est, verbose);
    } break;
    case CALIB_LAGRANGE:
    case CALIB_VIRTUAL_VS:
    case CALIB_LAGRANGE_VIRTUAL_VS:
    default:
      break;
    }
    // Print camera parameters
    if (verbose) {
      //       std::cout << "Camera parameters without distortion :" <<
      //       std::endl;
      this->cam.printParameters();
      //       std::cout << "Camera parameters with distortion :" <<
      //       std::endl;
      cam_est.printParameters();
    }

    this->cam_dist = cam_est;

    this->cMo_dist = cMo_est;

    if (cam_est.get_px() < 0 || cam_est.get_py() < 0 || cam_est.get_u0() < 0 || cam_est.get_v0() < 0) {
      std::cout << "Unable to calibrate the camera. Estimated parameters are negative." << std::endl;
      return EXIT_FAILURE;
    }

    return EXIT_SUCCESS;
  } catch (...) {
    throw;
  }
}

int vpCalibration::computeCalibrationMulti(vpCalibrationMethodType method, std::vector<vpCalibration> &table_cal,
                                           vpCameraParameters &cam_est, double &globalReprojectionError, bool verbose)
{
  try {
    unsigned int nbPose = (unsigned int)table_cal.size();
    for (unsigned int i = 0; i < nbPose; i++) {
      if (table_cal[i].get_npt() > 3)
        table_cal[i].computePose(cam_est, table_cal[i].cMo);
    }
    switch (method) {
    case CALIB_LAGRANGE: {
      if (nbPose > 1) {
        std::cout << "this calibration method is not available in" << std::endl
                  << "vpCalibration::computeCalibrationMulti()" << std::endl;
        return -1;
      } else {
        table_cal[0].calibLagrange(cam_est, table_cal[0].cMo);
        table_cal[0].cam = cam_est;
        table_cal[0].cam_dist = cam_est;
        table_cal[0].cMo_dist = table_cal[0].cMo;
      }
      break;
    }
    case CALIB_LAGRANGE_VIRTUAL_VS:
    case CALIB_LAGRANGE_VIRTUAL_VS_DIST: {
      if (nbPose > 1) {
        std::cout << "this calibration method is not available in" << std::endl
                  << "vpCalibration::computeCalibrationMulti()" << std::endl
                  << "with several images." << std::endl;
        return -1;
      } else {
        table_cal[0].calibLagrange(cam_est, table_cal[0].cMo);
        table_cal[0].cam = cam_est;
        table_cal[0].cam_dist = cam_est;
        table_cal[0].cMo_dist = table_cal[0].cMo;
      }
      calibVVSMulti(table_cal, cam_est, globalReprojectionError, verbose);
      break;
    }
    case CALIB_VIRTUAL_VS:
    case CALIB_VIRTUAL_VS_DIST: {
      calibVVSMulti(table_cal, cam_est, globalReprojectionError, verbose);
      break;
    }
    }
    // Print camera parameters
    if (verbose) {
      //       std::cout << "Camera parameters without distortion :" <<
      //       std::endl;
      cam_est.printParameters();
    }

    switch (method) {
    case CALIB_LAGRANGE:
    case CALIB_LAGRANGE_VIRTUAL_VS:
    case CALIB_VIRTUAL_VS:
      verbose = false;
      break;
    case CALIB_LAGRANGE_VIRTUAL_VS_DIST:
    case CALIB_VIRTUAL_VS_DIST: {
      if (verbose)
        std::cout << "Compute camera parameters with distortion" << std::endl;

      calibVVSWithDistortionMulti(table_cal, cam_est, globalReprojectionError, verbose);
    } break;
    }
    // Print camera parameters
    if (verbose) {
      //       std::cout << "Camera parameters without distortion :" <<
      //       std::endl;
      table_cal[0].cam.printParameters();
      //       std::cout << "Camera parameters with distortion:" << std::endl;
      cam_est.printParameters();
      std::cout << std::endl;
    }

    if (cam_est.get_px() < 0 || cam_est.get_py() < 0 || cam_est.get_u0() < 0 || cam_est.get_v0() < 0) {
      std::cout << "Unable to calibrate the camera. Estimated parameters are negative." << std::endl;
      return EXIT_FAILURE;
    }

    return EXIT_SUCCESS;
  } catch (...) {
    throw;
  }
}

int vpCalibration::writeData(const char *filename)
{
  std::ofstream f(filename);
  vpImagePoint ip;

  std::list<double>::const_iterator it_LoX = LoX.begin();
  std::list<double>::const_iterator it_LoY = LoY.begin();
  std::list<double>::const_iterator it_LoZ = LoZ.begin();
  std::list<vpImagePoint>::const_iterator it_Lip = Lip.begin();

  f.precision(10);
  f.setf(std::ios::fixed, std::ios::floatfield);
  f << LoX.size() << std::endl;

  for (unsigned int i = 0; i < LoX.size(); i++) {

    double oX = *it_LoX;
    double oY = *it_LoY;
    double oZ = *it_LoZ;

    ip = *it_Lip;
    double u = ip.get_u();
    double v = ip.get_v();

    f << oX << " " << oY << " " << oZ << " " << u << "  " << v << std::endl;

    ++it_LoX;
    ++it_LoY;
    ++it_LoZ;
    ++it_Lip;
  }

  f.close();
  return 0;
}

int vpCalibration::readData(const char *filename)
{
  vpImagePoint ip;
  std::ifstream f;
  f.open(filename);
  if (!f.fail()) {
    unsigned int n;
    f >> n;
    std::cout << "There are " << n << " point on the calibration grid " << std::endl;

    clearPoint();

    if (n > 100000)
      throw(vpException(vpException::badValue, "Bad number of point in the calibration grid"));

    for (unsigned int i = 0; i < n; i++) {
      double x, y, z, u, v;
      f >> x >> y >> z >> u >> v;
      std::cout << x << " " << y << " " << z << " " << u << " " << v << std::endl;
      ip.set_u(u);
      ip.set_v(v);
      addPoint(x, y, z, ip);
    }

    f.close();
    return 0;
  } else {
    return -1;
  }
}
int vpCalibration::readGrid(const char *filename, unsigned int &n, std::list<double> &oX, std::list<double> &oY,
                            std::list<double> &oZ, bool verbose)
{
  try {
    std::ifstream f;
    f.open(filename);
    if (!f.fail()) {

      f >> n;
      if (verbose)
        std::cout << "There are " << n << " points on the calibration grid " << std::endl;
      int no_pt;
      double x, y, z;

      // clear the list
      oX.clear();
      oY.clear();
      oZ.clear();

      if (n > 100000)
        throw(vpException(vpException::badValue, "Bad number of point in the calibration grid"));

      for (unsigned int i = 0; i < n; i++) {
        f >> no_pt >> x >> y >> z;
        if (verbose) {
          std::cout << no_pt << std::endl;
          std::cout << x << "  " << y << "  " << z << std::endl;
        }
        oX.push_back(x);
        oY.push_back(y);
        oZ.push_back(z);
      }

      f.close();
    } else {
      return -1;
    }
  } catch (...) {
    return -1;
  }
  return 0;
}

int vpCalibration::displayData(vpImage<unsigned char> &I, vpColor color, unsigned int thickness, int subsampling_factor)
{

  for (std::list<vpImagePoint>::const_iterator it = Lip.begin(); it != Lip.end(); ++it) {
    vpImagePoint ip = *it;
    if (subsampling_factor > 1.) {
      ip.set_u(ip.get_u() / subsampling_factor);
      ip.set_v(ip.get_v() / subsampling_factor);
    }
    vpDisplay::displayCross(I, ip, 12, color, thickness);
  }
  return 0;
}

int vpCalibration::displayGrid(vpImage<unsigned char> &I, vpColor color, unsigned int thickness, int subsampling_factor)
{
  double u0_dist = cam_dist.get_u0() / subsampling_factor;
  double v0_dist = cam_dist.get_v0() / subsampling_factor;
  double px_dist = cam_dist.get_px() / subsampling_factor;
  double py_dist = cam_dist.get_py() / subsampling_factor;
  double kud_dist = cam_dist.get_kud();
  //  double kdu_dist = cam_dist.get_kdu() ;

  //   double u0 = cam.get_u0() ;
  //   double v0 = cam.get_v0() ;
  //   double px = cam.get_px() ;
  //   double py = cam.get_py() ;

  std::list<double>::const_iterator it_LoX = LoX.begin();
  std::list<double>::const_iterator it_LoY = LoY.begin();
  std::list<double>::const_iterator it_LoZ = LoZ.begin();

  for (unsigned int i = 0; i < npt; i++) {
    double oX = *it_LoX;
    double oY = *it_LoY;
    double oZ = *it_LoZ;

    // double cX = oX*cMo[0][0]+oY*cMo[0][1]+oZ*cMo[0][2] + cMo[0][3];
    // double cY = oX*cMo[1][0]+oY*cMo[1][1]+oZ*cMo[1][2] + cMo[1][3];
    // double cZ = oX*cMo[2][0]+oY*cMo[2][1]+oZ*cMo[2][2] + cMo[2][3];

    // double x = cX/cZ ;
    // double y = cY/cZ ;

    //     double xp = u0 + x*px ;
    //     double yp = v0 + y*py ;

    //     vpDisplay::displayCross(I,(int)vpMath::round(yp),
    //     (int)vpMath::round(xp),
    //              5,col) ;

    double cX = oX * cMo_dist[0][0] + oY * cMo_dist[0][1] + oZ * cMo_dist[0][2] + cMo_dist[0][3];
    double cY = oX * cMo_dist[1][0] + oY * cMo_dist[1][1] + oZ * cMo_dist[1][2] + cMo_dist[1][3];
    double cZ = oX * cMo_dist[2][0] + oY * cMo_dist[2][1] + oZ * cMo_dist[2][2] + cMo_dist[2][3];

    double x = cX / cZ;
    double y = cY / cZ;

    double r2 = 1 + kud_dist * (vpMath::sqr(x) + vpMath::sqr(y));

    vpImagePoint ip;
    ip.set_u(u0_dist + x * px_dist * r2);
    ip.set_v(v0_dist + y * py_dist * r2);

    vpDisplay::displayCross(I, ip, 6, color, thickness);

    //    std::cout << oX << "  " << oY <<  "  " <<oZ << std::endl ;
    //    I.getClick() ;
    ++it_LoX;
    ++it_LoY;
    ++it_LoZ;
  }
  return 0;
}