gtsam/gtsam/geometry/Cal3DS2.h

/* ----------------------------------------------------------------------------

 * GTSAM Copyright 2010, Georgia Tech Research Corporation,
 * Atlanta, Georgia 30332-0415
 * All Rights Reserved
 * Authors: Frank Dellaert, et al. (see THANKS for the full author list)

 * See LICENSE for the license information

 * -------------------------------------------------------------------------- */

/**
 * @file Cal3DS2.h
 * @brief Calibration of a camera with radial distortion
 * @date Feb 28, 2010
 * @author ydjian
 */

#pragma once

#include <gtsam/base/DerivedValue.h>
#include <gtsam/geometry/Point2.h>

namespace gtsam {

/**
 * @brief Calibration of a camera with radial distortion
 * @addtogroup geometry
 * \nosubgrouping
 *
 * Uses same distortionmodel as OpenCV, with
 * http://docs.opencv.org/modules/calib3d/doc/camera_calibration_and_3d_reconstruction.html
 * but using only k1,k2,p1, and p2 coefficients.
 * K = [ fx s u0 ; 0 fy v0 ; 0 0 1 ]
 * rr = Pn.x^2 + Pn.y^2
 * \hat{pn} = (1 + k1*rr + k2*rr^2 ) pn + [ 2*k3 pn.x pn.y + k4 (rr + 2 Pn.x^2) ;
 *                      k3 (rr + 2 Pn.y^2) + 2*k4 pn.x pn.y  ]
 * pi = K*pn
 */
class GTSAM_EXPORT Cal3DS2 {

protected:

  double fx_, fy_, s_, u0_, v0_ ; // focal length, skew and principal point
  double k1_, k2_ ; // radial 2nd-order and 4th-order
  double p1_, p2_ ; // tangential distortion

public:

  Matrix K() const ;
  Eigen::Vector4d k() const { return Eigen::Vector4d(k1_, k2_, p1_, p2_); }
  Vector vector() const ;

  /// @name Standard Constructors
  /// @{

  /// Default Constructor with only unit focal length
  Cal3DS2() : fx_(1), fy_(1), s_(0), u0_(0), v0_(0), k1_(0), k2_(0), p1_(0), p2_(0) {}

  Cal3DS2(double fx, double fy, double s, double u0, double v0,
      double k1, double k2, double p1 = 0.0, double p2 = 0.0) :
  fx_(fx), fy_(fy), s_(s), u0_(u0), v0_(v0), k1_(k1), k2_(k2), p1_(p1), p2_(p2) {}

  /// @}
  /// @name Advanced Constructors
  /// @{

  Cal3DS2(const Vector &v) ;

  /// @}
  /// @name Testable
  /// @{

  /// print with optional string
  void print(const std::string& s = "") const ;

  /// assert equality up to a tolerance
  bool equals(const Cal3DS2& K, double tol = 10e-9) const;

  /// @}
  /// @name Standard Interface
  /// @{

  /// focal length x
  inline double fx() const { return fx_;}

  /// focal length x
  inline double fy() const { return fy_;}

  /// skew
  inline double skew() const { return s_;}

  /// image center in x
  inline double px() const { return u0_;}

  /// image center in y
  inline double py() const { return v0_;}

  /// First distortion coefficient
  inline double k1() const { return k1_;}

  /// Second distortion coefficient
  inline double k2() const { return k2_;}

  /// First tangential distortion coefficient
  inline double p1() const { return p1_;}

  /// Second tangential distortion coefficient
  inline double p2() const { return p2_;}

  /**
   * convert intrinsic coordinates xy to (distorted) image coordinates uv
   * @param p point in intrinsic coordinates
   * @param Dcal optional 2*9 Jacobian wrpt Cal3DS2 parameters
   * @param Dp optional 2*2 Jacobian wrpt intrinsic coordinates
   * @return point in (distorted) image coordinates
   */
  Point2 uncalibrate(const Point2& p,
      boost::optional<Matrix&> Dcal = boost::none,
      boost::optional<Matrix&> Dp = boost::none) const ;

  /// Convert (distorted) image coordinates uv to intrinsic coordinates xy
  Point2 calibrate(const Point2& p, const double tol=1e-5) const;

  /// Derivative of uncalibrate wrpt intrinsic coordinates
  Matrix D2d_intrinsic(const Point2& p) const ;

  /// Derivative of uncalibrate wrpt the calibration parameters
  Matrix D2d_calibration(const Point2& p) const ;

  /// @}
  /// @name Manifold
  /// @{

  /// Given delta vector, update calibration
  Cal3DS2 retract(const Vector& d) const ;

  /// Given a different calibration, calculate update to obtain it
  Vector localCoordinates(const Cal3DS2& T2) const ;

  /// Return dimensions of calibration manifold object
  virtual size_t dim() const { return 9 ; } //TODO: make a final dimension variable (also, usually size_t in other classes e.g. Pose2)

  /// Return dimensions of calibration manifold object
  static size_t Dim() { return 9; }  //TODO: make a final dimension variable

  /// @}

private:

  /** Serialization function */
  friend class boost::serialization::access;
  template<class Archive>
  void serialize(Archive & ar, const unsigned int version)
  {
    ar & BOOST_SERIALIZATION_NVP(fx_);
    ar & BOOST_SERIALIZATION_NVP(fy_);
    ar & BOOST_SERIALIZATION_NVP(s_);
    ar & BOOST_SERIALIZATION_NVP(u0_);
    ar & BOOST_SERIALIZATION_NVP(v0_);
    ar & BOOST_SERIALIZATION_NVP(k1_);
    ar & BOOST_SERIALIZATION_NVP(k2_);
    ar & BOOST_SERIALIZATION_NVP(p1_);
    ar & BOOST_SERIALIZATION_NVP(p2_);
  }

};

// Define GTSAM traits
namespace traits {

template<>
struct is_manifold<Cal3DS2> : public boost::true_type {
};

template<>
struct dimension<Cal3DS2> : public boost::integral_constant<int, 9> {
};

}

}