gtsam/gtsam_unstable/examples/SmartStereoProjectionFactor...

154 lines
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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 SmartProjectionFactorExample.cpp
* @brief A stereo visual odometry example
* @date May 30, 2014
* @author Stephen Camp
* @author Chris Beall
*/
/**
* A smart projection factor example based on stereo data, throwing away the
* measurement from the right camera
* -robot starts at origin
* -moves forward, taking periodic stereo measurements
* -makes monocular observations of many landmarks
*/
#include <gtsam/geometry/Pose3.h>
#include <gtsam/geometry/Cal3_S2Stereo.h>
#include <gtsam/nonlinear/Values.h>
#include <gtsam/nonlinear/NonlinearEquality.h>
#include <gtsam/nonlinear/NonlinearFactorGraph.h>
#include <gtsam/nonlinear/LevenbergMarquardtOptimizer.h>
#include <gtsam/inference/Symbol.h>
#include <gtsam/slam/dataset.h>
#include <gtsam/slam/SmartStereoProjectionPoseFactor.h>
#include <string>
#include <fstream>
#include <iostream>
using namespace std;
using namespace gtsam;
int main(int argc, char** argv){
typedef SmartStereoProjectionPoseFactor<Pose3, Point3, Cal3_S2Stereo> SmartFactor;
bool output_poses = true;
bool output_initial_poses = true;
string poseOutput("../../../examples/data/optimized_poses.txt");
string init_poseOutput("../../../examples/data/initial_poses.txt");
Values initial_estimate;
NonlinearFactorGraph graph;
const noiseModel::Isotropic::shared_ptr model = noiseModel::Isotropic::Sigma(3,1);
ofstream pose3Out, init_pose3Out;
bool add_initial_noise = true;
string calibration_loc = findExampleDataFile("VO_calibration.txt");
string pose_loc = findExampleDataFile("VO_camera_poses_large.txt");
string factor_loc = findExampleDataFile("VO_stereo_factors_large.txt");
//read camera calibration info from file
// focal lengths fx, fy, skew s, principal point u0, v0, baseline b
cout << "Reading calibration info" << endl;
ifstream calibration_file(calibration_loc.c_str());
double fx, fy, s, u0, v0, b;
calibration_file >> fx >> fy >> s >> u0 >> v0 >> b;
const Cal3_S2Stereo::shared_ptr K(new Cal3_S2Stereo(fx, fy, s, u0, v0,b));
cout << "Reading camera poses" << endl;
ifstream pose_file(pose_loc.c_str());
int pose_id;
MatrixRowMajor m(4,4);
//read camera pose parameters and use to make initial estimates of camera poses
while (pose_file >> pose_id) {
for (int i = 0; i < 16; i++) {
pose_file >> m.data()[i];
}
if(add_initial_noise){
m(1,3) += (pose_id % 10)/10.0;
}
initial_estimate.insert(Symbol('x', pose_id), Pose3(m));
}
Values initial_pose_values = initial_estimate.filter<Pose3>();
if(output_poses){
init_pose3Out.open(init_poseOutput.c_str(),ios::out);
for(int i = 1; i<=initial_pose_values.size(); i++){
init_pose3Out << i << " " << initial_pose_values.at<Pose3>(Symbol('x',i)).matrix().format(Eigen::IOFormat(Eigen::StreamPrecision, 0,
" ", " ")) << endl;
}
}
// camera and landmark keys
size_t x, l;
// pixel coordinates uL, uR, v (same for left/right images due to rectification)
// landmark coordinates X, Y, Z in camera frame, resulting from triangulation
double uL, uR, v, X, Y, Z;
ifstream factor_file(factor_loc.c_str());
cout << "Reading stereo factors" << endl;
//read stereo measurements and construct smart factors
SmartFactor::shared_ptr factor(new SmartFactor());
size_t current_l = 3; // hardcoded landmark ID from first measurement
while (factor_file >> x >> l >> uL >> uR >> v >> X >> Y >> Z) {
if(current_l != l) {
graph.push_back(factor);
factor = SmartFactor::shared_ptr(new SmartFactor());
current_l = l;
}
factor->add(StereoPoint2(uL,uR,v), Symbol('x',x), model, K);
}
Pose3 first_pose = initial_estimate.at<Pose3>(Symbol('x',1));
//constrain the first pose such that it cannot change from its original value during optimization
// NOTE: NonlinearEquality forces the optimizer to use QR rather than Cholesky
// QR is much slower than Cholesky, but numerically more stable
graph.push_back(NonlinearEquality<Pose3>(Symbol('x',1),first_pose));
LevenbergMarquardtParams params;
params.verbosityLM = LevenbergMarquardtParams::TRYLAMBDA;
params.verbosity = NonlinearOptimizerParams::ERROR;
cout << "Optimizing" << endl;
//create Levenberg-Marquardt optimizer to optimize the factor graph
LevenbergMarquardtOptimizer optimizer = LevenbergMarquardtOptimizer(graph, initial_estimate, params);
Values result = optimizer.optimize();
cout << "Final result sample:" << endl;
Values pose_values = result.filter<Pose3>();
pose_values.print("Final camera poses:\n");
if(output_poses){
pose3Out.open(poseOutput.c_str(),ios::out);
for(int i = 1; i<=pose_values.size(); i++){
pose3Out << i << " " << pose_values.at<Pose3>(Symbol('x',i)).matrix().format(Eigen::IOFormat(Eigen::StreamPrecision, 0,
" ", " ")) << endl;
}
cout << "Writing output" << endl;
}
return 0;
}