103 lines
3.5 KiB
C++
103 lines
3.5 KiB
C++
/* ----------------------------------------------------------------------------
|
|
|
|
* 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 CameraResectioning.cpp
|
|
* @brief An example of gtsam for solving the camera resectioning problem
|
|
* @author Duy-Nguyen Ta
|
|
* @date Aug 23, 2011
|
|
*/
|
|
|
|
#include <gtsam/nonlinear/Symbol.h>
|
|
#include <gtsam/geometry/Pose3.h>
|
|
#include <gtsam/geometry/Cal3_S2.h>
|
|
#include <gtsam/geometry/SimpleCamera.h>
|
|
#include <gtsam/nonlinear/NonlinearFactor.h>
|
|
#include <gtsam/nonlinear/NonlinearFactorGraph.h>
|
|
#include <gtsam/nonlinear/LevenbergMarquardtOptimizer.h>
|
|
|
|
using namespace gtsam;
|
|
|
|
/**
|
|
* Unary factor for the pose.
|
|
*/
|
|
class ResectioningFactor: public NoiseModelFactor1<Pose3> {
|
|
typedef NoiseModelFactor1<Pose3> Base;
|
|
|
|
shared_ptrK K_; // camera's intrinsic parameters
|
|
Point3 P_; // 3D point on the calibration rig
|
|
Point2 p_; // 2D measurement of the 3D point
|
|
|
|
public:
|
|
ResectioningFactor(const SharedNoiseModel& model, const Symbol& key,
|
|
const shared_ptrK& calib, const Point2& p, const Point3& P) :
|
|
Base(model, key), K_(calib), P_(P), p_(p) {
|
|
}
|
|
|
|
virtual ~ResectioningFactor() {}
|
|
|
|
virtual Vector evaluateError(const Pose3& X, boost::optional<Matrix&> H = boost::none) const {
|
|
SimpleCamera camera(*K_, X);
|
|
Point2 reprojectionError(camera.project(P_, H) - p_);
|
|
return reprojectionError.vector();
|
|
}
|
|
};
|
|
|
|
/*******************************************************************************/
|
|
/**
|
|
* Camera: f = 1.0, Image: 100x100, center: 50.0, 50.0
|
|
* Pose (ground truth): (Xw, -Yw, -Zw, [0,0,2.0]')
|
|
* Known landmarks:
|
|
* 3D Points: (10,10,0) (-10,10,0) (-10,-10,0) (10,-10,0)
|
|
* Perfect measurements:
|
|
* 2D Point: (55,45) (45,45) (45,55) (55,55)
|
|
*/
|
|
int main(int argc, char* argv[]) {
|
|
/* read camera intrinsic parameters */
|
|
shared_ptrK calib(new Cal3_S2(1.0, 1.0, 0, 50.0, 50.0));
|
|
|
|
/* create keys for variables */
|
|
// we have only 1 variable to solve: the camera pose
|
|
Symbol X('x',1);
|
|
|
|
/* 1. create graph */
|
|
NonlinearFactorGraph graph;
|
|
|
|
/* 2. add factors to the graph */
|
|
// add measurement factors
|
|
SharedDiagonal measurementNoise = sharedSigmas(Vector_(2, 0.5, 0.5));
|
|
boost::shared_ptr<ResectioningFactor> factor;
|
|
factor = boost::shared_ptr<ResectioningFactor>(new ResectioningFactor(
|
|
measurementNoise, X, calib, Point2(55.0, 45.0), Point3(10.0, 10.0, 0.0)));
|
|
graph.push_back(factor);
|
|
factor = boost::shared_ptr<ResectioningFactor>(new ResectioningFactor(
|
|
measurementNoise, X, calib, Point2(45.0, 45.0), Point3(-10.0, 10.0, 0.0)));
|
|
graph.push_back(factor);
|
|
factor = boost::shared_ptr<ResectioningFactor>(new ResectioningFactor(
|
|
measurementNoise, X, calib, Point2(45.0, 55.0), Point3(-10.0, -10.0, 0.0)));
|
|
graph.push_back(factor);
|
|
factor = boost::shared_ptr<ResectioningFactor>(new ResectioningFactor(
|
|
measurementNoise, X, calib, Point2(55.0, 55.0), Point3(10.0, -10.0, 0.0)));
|
|
graph.push_back(factor);
|
|
|
|
/* 3. Create an initial estimate for the camera pose */
|
|
Values initial;
|
|
initial.insert(X, Pose3(Rot3(1.,0.,0.,
|
|
0.,-1.,0.,
|
|
0.,0.,-1.), Point3(0.,0.,2.0)));
|
|
|
|
/* 4. Optimize the graph using Levenberg-Marquardt*/
|
|
Values result = *LevenbergMarquardtOptimizer(graph, initial).optimized();
|
|
result.print("Final result: ");
|
|
|
|
return 0;
|
|
}
|