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#include <opencv2/sfm.hpp>
#include <opencv2/core.hpp>
#include <opencv2/viz.hpp>
#include <iostream>
#include <fstream>
#include <string>
using namespace std;
using namespace cv;
using namespace cv::sfm;
static void help() {
cout
<< "\n------------------------------------------------------------------\n"
<< " This program shows the two view reconstruction capabilities in the \n"
<< " OpenCV Structure From Motion (SFM) module.\n"
<< " It uses the following data from the VGG datasets at ...\n"
<< " Usage:\n"
<< " reconv2_pts.txt \n "
<< " where the first line has the number of points and each subsequent \n"
<< " line has entries for matched points as: \n"
<< " x1 y1 x2 y2 \n"
<< "------------------------------------------------------------------\n\n"
<< endl;
}
int main(int argc, char** argv)
{
// Do projective reconstruction
bool is_projective = true;
// Read 2D points from text file
Mat_<double> x1, x2;
int npts;
if (argc < 2) {
help();
exit(0);
} else {
ifstream myfile(argv[1]);
if (!myfile.is_open()) {
cout << "Unable to read file: " << argv[1] << endl;
exit(0);
} else {
string line;
// Read number of points
getline(myfile, line);
npts = (int) atof(line.c_str());
x1 = Mat_<double>(2, npts);
x2 = Mat_<double>(2, npts);
// Read the point coordinates
for (int i = 0; i < npts; ++i) {
getline(myfile, line);
stringstream s(line);
string cord;
s >> cord;
x1(0, i) = atof(cord.c_str());
s >> cord;
x1(1, i) = atof(cord.c_str());
s >> cord;
x2(0, i) = atof(cord.c_str());
s >> cord;
x2(1, i) = atof(cord.c_str());
}
myfile.close();
}
}
// Call the reconstruction function
std::vector < Mat_<double> > points2d;
points2d.push_back(x1);
points2d.push_back(x2);
Matx33d K_estimated;
Mat_<double> points3d_estimated;
std::vector < cv::Mat > Ps_estimated;
reconstruct(points2d, Ps_estimated, points3d_estimated, K_estimated, is_projective);
// Print output
cout << endl;
cout << "Projection Matrix of View 1: " << endl;
cout << "============================ " << endl;
cout << Ps_estimated[0] << endl << endl;
cout << "Projection Matrix of View 2: " << endl;
cout << "============================ " << endl;
cout << Ps_estimated[1] << endl << endl;
// Display 3D points using VIZ module
// Create the pointcloud
std::vector<cv::Vec3f> point_cloud;
for (int i = 0; i < npts; ++i) {
cv::Vec3f point3d((float) points3d_estimated(0, i),
(float) points3d_estimated(1, i),
(float) points3d_estimated(2, i));
point_cloud.push_back(point3d);
}
// Create a 3D window
viz::Viz3d myWindow("Coordinate Frame");
/// Add coordinate axes
myWindow.showWidget("Coordinate Widget", viz::WCoordinateSystem());
viz::WCloud cloud_widget(point_cloud, viz::Color::green());
myWindow.showWidget("cloud", cloud_widget);
myWindow.spin();
return 0;
}