assuming that both have the same value. Then the cameraMatrix is updated with the estimated
focal length.
- **SOLVEPNP_AP3P** Method is based on the paper of Tong Ke and Stergios I. Roumeliotis.
-"An Efficient Algebraic Solution to the Perspective-Three-Point Problem". In this case the
+"An Efficient Algebraic Solution to the Perspective-Three-Point Problem" (@cite Ke17). In this case the
function requires exactly four object and image points.
The function estimates the object pose given a set of object points, their corresponding image
- The methods **SOLVEPNP_DLS** and **SOLVEPNP_UPNP** cannot be used as the current implementations are
unstable and sometimes give completely wrong results. If you pass one of these two
flags, **SOLVEPNP_EPNP** method will be used instead.
- - The minimum number of points is 4. In the case of **SOLVEPNP_P3P** and **SOLVEPNP_AP3P**
+ - The minimum number of points is 4 in the general case. In the case of **SOLVEPNP_P3P** and **SOLVEPNP_AP3P**
methods, it is required to use exactly 4 points (the first 3 points are used to estimate all the solutions
of the P3P problem, the last one is used to retain the best solution that minimizes the reprojection error).
+ - With **SOLVEPNP_ITERATIVE** method and `useExtrinsicGuess=true`, the minimum number of points is 3 (3 points
+ are sufficient to compute a pose but there are up to 4 solutions). The initial solution should be close to the
+ global solution to converge.
*/
CV_EXPORTS_W bool solvePnP( InputArray objectPoints, InputArray imagePoints,
InputArray cameraMatrix, InputArray distCoeffs,
@param tvecs Output translation vectors.
@param flags Method for solving a P3P problem:
- **SOLVEPNP_P3P** Method is based on the paper of X.S. Gao, X.-R. Hou, J. Tang, H.-F. Chang
-"Complete Solution Classification for the Perspective-Three-Point Problem".
+"Complete Solution Classification for the Perspective-Three-Point Problem" (@cite gao2003complete).
- **SOLVEPNP_AP3P** Method is based on the paper of Tong Ke and Stergios I. Roumeliotis.
-"An Efficient Algebraic Solution to the Perspective-Three-Point Problem".
+"An Efficient Algebraic Solution to the Perspective-Three-Point Problem" (@cite Ke17).
The function estimates the object pose given 3 object points, their corresponding image
projections, as well as the camera matrix and the distortion coefficients.
if (num_of_solutions != (int) rvecs.size() || num_of_solutions != (int) tvecs.size() || num_of_solutions == 0)
return false;
- double min_rvecDiff = DBL_MAX, min_tvecDiff = DBL_MAX;
- for (unsigned int i = 0; i < rvecs.size(); ++i) {
+ bool isTestSuccess = false;
+ double error = DBL_MAX;
+ for (unsigned int i = 0; i < rvecs.size() && !isTestSuccess; ++i) {
double rvecDiff = norm(rvecs[i]-trueRvec);
- min_rvecDiff = std::min(rvecDiff, min_rvecDiff);
- }
- for (unsigned int i = 0; i < tvecs.size(); ++i) {
double tvecDiff = norm(tvecs[i]-trueTvec);
- min_tvecDiff = std::min(tvecDiff, min_tvecDiff);
+ isTestSuccess = rvecDiff < epsilon[method] && tvecDiff < epsilon[method];
+ error = std::min(error, std::max(rvecDiff, tvecDiff));
}
- bool isTestSuccess = min_rvecDiff < epsilon[method] && min_tvecDiff < epsilon[method];
- double error = std::max(min_rvecDiff, min_tvecDiff);
if (error > maxError)
maxError = error;
{
ts->set_failed_test_info(cvtest::TS::OK);
- vector<Point3f> points, points_dls;
+ vector<Point3f> points;
points.resize(pointsCount);
generate3DPointCloud(points);
EXPECT_TRUE(checkRange(rvec));
EXPECT_TRUE(checkRange(tvec));
}
+
+TEST(Calib3d_SolvePnP, iterativeInitialGuess3pts)
+{
+ {
+ Matx33d intrinsics(605.4, 0.0, 317.35,
+ 0.0, 601.2, 242.63,
+ 0.0, 0.0, 1.0);
+
+ double L = 0.1;
+ vector<Point3d> p3d;
+ p3d.push_back(Point3d(-L, -L, 0.0));
+ p3d.push_back(Point3d(L, -L, 0.0));
+ p3d.push_back(Point3d(L, L, 0.0));
+
+ Mat rvec_ground_truth = (Mat_<double>(3,1) << 0.3, -0.2, 0.75);
+ Mat tvec_ground_truth = (Mat_<double>(3,1) << 0.15, -0.2, 1.5);
+
+ vector<Point2d> p2d;
+ projectPoints(p3d, rvec_ground_truth, tvec_ground_truth, intrinsics, noArray(), p2d);
+
+ Mat rvec_est = (Mat_<double>(3,1) << 0.2, -0.1, 0.6);
+ Mat tvec_est = (Mat_<double>(3,1) << 0.05, -0.05, 1.0);
+
+ solvePnP(p3d, p2d, intrinsics, noArray(), rvec_est, tvec_est, true, SOLVEPNP_ITERATIVE);
+
+ std::cout << "rvec_ground_truth: " << rvec_ground_truth.t() << std::endl;
+ std::cout << "rvec_est: " << rvec_est.t() << std::endl;
+ std::cout << "tvec_ground_truth: " << tvec_ground_truth.t() << std::endl;
+ std::cout << "tvec_est: " << tvec_est.t() << std::endl;
+
+ EXPECT_LE(norm(rvec_ground_truth, rvec_est, NORM_INF), 1e-6);
+ EXPECT_LE(norm(tvec_ground_truth, tvec_est, NORM_INF), 1e-6);
+ }
+
+ {
+ Matx33f intrinsics(605.4f, 0.0f, 317.35f,
+ 0.0f, 601.2f, 242.63f,
+ 0.0f, 0.0f, 1.0f);
+
+ float L = 0.1f;
+ vector<Point3f> p3d;
+ p3d.push_back(Point3f(-L, -L, 0.0f));
+ p3d.push_back(Point3f(L, -L, 0.0f));
+ p3d.push_back(Point3f(L, L, 0.0f));
+
+ Mat rvec_ground_truth = (Mat_<float>(3,1) << -0.75f, 0.4f, 0.34f);
+ Mat tvec_ground_truth = (Mat_<float>(3,1) << -0.15f, 0.35f, 1.58f);
+
+ vector<Point2f> p2d;
+ projectPoints(p3d, rvec_ground_truth, tvec_ground_truth, intrinsics, noArray(), p2d);
+
+ Mat rvec_est = (Mat_<float>(3,1) << -0.5f, 0.2f, 0.2f);
+ Mat tvec_est = (Mat_<float>(3,1) << 0.0f, 0.2f, 1.0f);
+
+ solvePnP(p3d, p2d, intrinsics, noArray(), rvec_est, tvec_est, true, SOLVEPNP_ITERATIVE);
+
+ std::cout << "rvec_ground_truth: " << rvec_ground_truth.t() << std::endl;
+ std::cout << "rvec_est: " << rvec_est.t() << std::endl;
+ std::cout << "tvec_ground_truth: " << tvec_ground_truth.t() << std::endl;
+ std::cout << "tvec_est: " << tvec_est.t() << std::endl;
+
+ EXPECT_LE(norm(rvec_ground_truth, rvec_est, NORM_INF), 1e-6);
+ EXPECT_LE(norm(tvec_ground_truth, tvec_est, NORM_INF), 1e-6);
+ }
+}