reformulated irradiance to be: irradiance arround measured feature - irradiance at projection

include/msckf_vio/feature.hpp

@@ -173,7 +173,7 @@ struct Feature {
                   std::vector<double>& anchorPatch_estimate,
                   IlluminationParameter& estimatedIllumination) const;
 
-bool MarkerGeneration(
+  bool MarkerGeneration(
                   ros::Publisher& marker_pub,
                   const CamStateServer& cam_states) const;
 
@@ -183,6 +183,17 @@ bool MarkerGeneration(
                   CameraCalibration& cam0,
                   const std::vector<double> photo_r,
                   std::stringstream& ss) const;
+  
+
+  /* @brief takes a pure pixel position (1m from image)
+  * converts to actual pixel value and returns patch irradiance
+  * around this pixel
+  */
+  void PatchAroundPurePixel(cv::Point2f p, 
+                               int N,
+                               const CameraCalibration& cam, 
+                               const StateIDType& cam_state_id,
+                               std::vector<float>& return_i) const;
   /*
   * @brief projectPixelToPosition uses the calcualted pixels
   *     of the anchor patch to generate 3D positions of all of em
@@ -665,6 +676,25 @@ bool Feature::VisualizePatch(
   cvWaitKey(0);
 }
 
+void Feature::PatchAroundPurePixel(cv::Point2f p, 
+                               int N,
+                               const CameraCalibration& cam, 
+                               const StateIDType& cam_state_id,
+                               std::vector<float>& return_i) const
+{
+  int n = (int)(N-1)/2;
+  cv::Mat image = cam.moving_window.find(cam_state_id)->second.image;
+  cv::Point2f img_p = image_handler::distortPoint(p, 
+                                                cam.intrinsics, 
+                                                cam.distortion_model, 
+                                                cam.distortion_coeffs);
+
+  for(double u_run = -n; u_run <= n; u_run++)
+    for(double v_run = -n; v_run <= n; v_run++)
+      return_i.push_back(PixelIrradiance(cv::Point2f(img_p.x+u_run, img_p.y+v_run), image));
+
+}
+
 float Feature::PixelIrradiance(cv::Point2f pose, cv::Mat image) const
 {
 

src/msckf_vio.cpp

@@ -1229,163 +1229,74 @@ void MsckfVio::PhotometricMeasurementJacobian(
   Matrix3d R_w_c0 = quaternionToRotation(cam_state.orientation);
   const Vector3d& t_c0_w = cam_state.position;
 
-  // Cam1 pose.
-  Matrix3d R_c0_c1 = CAMState::T_cam0_cam1.linear();
-  Matrix3d R_w_c1 = CAMState::T_cam0_cam1.linear() * R_w_c0;
-  Vector3d t_c1_w = t_c0_w - R_w_c1.transpose()*CAMState::T_cam0_cam1.translation();
-
-
-  //photometric observation
-  std::vector<double> photo_z;
-
-  // individual Jacobians
-  Matrix<double, 1, 2> dI_dhj = Matrix<double, 1, 2>::Zero();
-  Matrix<double, 2, 3> dh_dCpij = Matrix<double, 2, 3>::Zero();
-  Matrix<double, 2, 3> dh_dGpij = Matrix<double, 2, 3>::Zero();
-  Matrix<double, 2, 6> dh_dXplj = Matrix<double, 2, 6>::Zero();
-  Matrix<double, 3, 1> dGpj_drhoj = Matrix<double, 3, 1>::Zero();
-  Matrix<double, 3, 6> dGpj_XpAj = Matrix<double, 3, 6>::Zero();
-
-  Matrix<double, 3, 3> dCpij_dGpij = Matrix<double, 3, 3>::Zero();
-  Matrix<double, 3, 3> dCpij_dCGtheta = Matrix<double, 3, 3>::Zero();
-  Matrix<double, 3, 3> dCpij_dGpC = Matrix<double, 3, 3>::Zero();
-
   // one line of the NxN Jacobians
-  Eigen::Matrix<double, 1, 1> H_rhoj;
+  Matrix<double, 1, 6> H_xi;
-  Eigen::Matrix<double, 1, 6> H_plj;
+  Matrix<double, 1, 3> H_fi;
-  Eigen::Matrix<double, 1, 6> H_pAj;
 
-  // combined Jacobians
+  MatrixXd H_xl = MatrixXd::Zero(feature.anchorPatch_3d.size(), 6);
-  Eigen::MatrixXd H_rho(N*N, 1);
+  MatrixXd H_yl = MatrixXd::Zero(feature.anchorPatch_3d.size(), 3);
-  Eigen::MatrixXd H_pl(N*N, 6);
-  Eigen::MatrixXd H_pA(N*N, 6);
 
   auto frame = cam0.moving_window.find(cam_state_id)->second.image;
 
   int count = 0;
   double dx, dy;
 
+  std::vector<float> z_irr_est;
+
   for (auto point : feature.anchorPatch_3d)
   {
     Eigen::Vector3d p_c0 = R_w_c0 * (point-t_c0_w);
     cv::Point2f p_in_c0 = feature.projectPositionToCamera(cam_state, cam_state_id, cam0, point);
 
-    //add observation
+    z_irr_est.push_back(feature.PixelIrradiance(p_in_c0, frame));
-    photo_z.push_back(feature.PixelIrradiance(p_in_c0, frame));
 
-    // add jacobian
+    Matrix<double, 1, 2> dI_dhj = Matrix<double, 1, 2>::Zero();
 
     // frame derivative calculated convoluting with kernel [-1, 0, 1]
     dx = feature.PixelIrradiance(cv::Point2f(p_in_c0.x+1, p_in_c0.y), frame) - feature.PixelIrradiance(cv::Point2f(p_in_c0.x-1, p_in_c0.y), frame);
     dy = feature.PixelIrradiance(cv::Point2f(p_in_c0.x, p_in_c0.y+1), frame) - feature.PixelIrradiance(cv::Point2f(p_in_c0.x, p_in_c0.y-1), frame);
     dI_dhj(0, 0) = dx;
     dI_dhj(0, 1) = dy;
+
+    // Compute the Jacobians.
+    Matrix<double, 2, 3> dz_dpc0 = Matrix<double, 2, 3>::Zero();
+    dz_dpc0(0, 0) = 1 / p_c0(2);
+    dz_dpc0(1, 1) = 1 / p_c0(2);
+    dz_dpc0(0, 2) = -p_c0(0) / (p_c0(2)*p_c0(2));
+    dz_dpc0(1, 2) = -p_c0(1) / (p_c0(2)*p_c0(2));
+
+    Matrix<double, 3, 6> dpc0_dxc = Matrix<double, 3, 6>::Zero();
     
-    //dh / d{}^Cp_{ij}
+    // original jacobi
-    dh_dCpij(0, 0) = 1 / p_c0(2);
+    dpc0_dxc.leftCols(3) = skewSymmetric(p_c0);
-    dh_dCpij(1, 1) = 1 / p_c0(2);
+    dpc0_dxc.rightCols(3) = -R_w_c0;
-    dh_dCpij(0, 2) = -(p_c0(0))/(p_c0(2)*p_c0(2));
-    dh_dCpij(1, 2) = -(p_c0(1))/(p_c0(2)*p_c0(2));
 
-    dCpij_dGpij = quaternionToRotation(cam_state.orientation);
+    Matrix3d dpc0_dpg = R_w_c0;
 
-    //orientation takes camera frame to world frame, we wa
+    H_xi = dI_dhj*dz_dpc0*dpc0_dxc;
-    dh_dGpij = dh_dCpij * dCpij_dGpij;
+    H_fi = dI_dhj*dz_dpc0*dpc0_dpg;
 
-    //dh / d X_{pl}
+    H_xl.block<1, 6>(count, 0) = H_xi;
-    dCpij_dCGtheta = skewSymmetric(p_c0);
+    H_yl.block<1, 3>(count, 0) = H_fi;
-    dCpij_dGpC = -quaternionToRotation(cam_state.orientation);
-    dh_dXplj.block<2, 3>(0, 0) = dh_dCpij * dCpij_dCGtheta;
-    dh_dXplj.block<2, 3>(0, 3) = dh_dCpij * dCpij_dGpC;
-
-    //d{}^Gp_P{ij} / \rho_i
-    double rho = feature.anchor_rho;
-    // Isometry T_anchor_w takes a vector in anchor frame to world frame
-    dGpj_drhoj = -feature.T_anchor_w.linear() * Eigen::Vector3d(feature.anchorPatch_ideal[count].x/(rho*rho), feature.anchorPatch_ideal[count].y/(rho*rho), 1/(rho*rho));
-
-    dGpj_XpAj.block<3, 3>(0, 0) = - feature.T_anchor_w.linear()
-                                 * skewSymmetric(Eigen::Vector3d(feature.anchorPatch_ideal[count].x/(rho), 
-                                                   feature.anchorPatch_ideal[count].y/(rho), 
-                                                   1/(rho)));
-    dGpj_XpAj.block<3, 3>(0, 3) = Matrix<double, 3, 3>::Identity();
-
-    // Intermediate Jakobians
-    H_rhoj = dI_dhj * dh_dGpij * dGpj_drhoj; // 1 x 1
-    H_plj = dI_dhj * dh_dXplj; // 1 x 6
-    H_pAj = dI_dhj * dh_dGpij * dGpj_XpAj; // 1 x 6
-
-    H_rho.block<1, 1>(count, 0) = H_rhoj;
-    H_pl.block<1, 6>(count, 0) = H_plj;
-    H_pA.block<1, 6>(count, 0) = H_pAj;
 
     count++;
   }
-  // calculate residual
 
-  //observation
+  // Compute the residual.
-  const Vector4d& z = feature.observations.find(cam_state_id)->second;
+  std::vector<float> z_irr;
+  cv::Point2f z = cv::Point2f(feature.observations.find(cam_state_id)->second(0), feature.observations.find(cam_state_id)->second(1));
+  feature.PatchAroundPurePixel(z, N, cam0, cam_state_id, z_irr);
 
-  //estimate photometric measurement
+  Eigen::VectorXd r_l = Eigen::VectorXd::Zero(count-1);
-  std::vector<double> estimate_irradiance;
-  std::vector<double> estimate_photo_z;
-  IlluminationParameter estimated_illumination;
-  feature.estimate_FrameIrradiance(cam_state, cam_state_id, cam0, estimate_irradiance, estimated_illumination);
-  
-  // calculated here, because we need true 'estimate_irradiance' later for jacobi
-  for (auto& estimate_irradiance_j : estimate_irradiance)
-            estimate_photo_z.push_back (estimate_irradiance_j * 
-                    estimated_illumination.frame_gain * estimated_illumination.feature_gain +
-                    estimated_illumination.frame_bias + estimated_illumination.feature_bias);
 
-  std::vector<double> photo_r;
+  for(int i = 0; i < r_l.size(); i++)
-  
+    r_l(i) = z_irr[i]- z_irr_est[i];
-  //calculate photom. residual
-  for(int i = 0; i < photo_z.size(); i++)
-    photo_r.push_back(photo_z[i] - estimate_photo_z[i]);
 
-  MatrixXd H_xl = MatrixXd::Zero(N*N, 21+state_server.cam_states.size()*7);
-  MatrixXd H_yl = MatrixXd::Zero(N*N, N*N+state_server.cam_states.size()+1);
-
-  // set anchor Jakobi
-    // get position of anchor in cam states
-
-  auto cam_state_anchor = state_server.cam_states.find(feature.observations.begin()->first);
-  int cam_state_cntr_anchor = std::distance(state_server.cam_states.begin(), cam_state_anchor);
-  H_xl.block(0, 21+cam_state_cntr_anchor*7, N*N, 6) = -H_pA; 
-
-  // set frame Jakobi
-    //get position of current frame in cam states
-  auto cam_state_iter = state_server.cam_states.find(cam_state_id);
-  int cam_state_cntr = std::distance(state_server.cam_states.begin(), cam_state_iter);
-  
-    // set jakobi of state
-  H_xl.block(0, 21+cam_state_cntr*7, N*N, 6) = -H_pl;
-
-    // set ones for irradiance bias
-  H_xl.block(0, 21+cam_state_cntr*7+6, N*N, 1) = Eigen::ArrayXd::Ones(N*N);
-
-  // set irradiance error Block
-  H_yl.block(0, 0,N*N, N*N) = estimated_illumination.feature_gain * estimated_illumination.frame_gain * Eigen::MatrixXd::Identity(N*N, N*N);
-  
-  // TODO make this calculation more fluent
-  for(int i = 0; i< N*N; i++)
-    H_yl(i, N*N+cam_state_cntr) = estimate_irradiance[i];
-  H_yl.block(0, N*N+state_server.cam_states.size(), N*N, 1) = -H_rho;
 
+  r = r_l;
   H_x = H_xl;
   H_y = H_yl;
-
+  // calculate residual
-  //TODO make this more fluent as well
-  count = 0; 
-  for(auto data : photo_r)
-    r[count++] = data;
-  std::stringstream ss;
-  ss << "INFO:" << " anchor: " << cam_state_cntr_anchor << "  frame: " << cam_state_cntr;
-  if(PRINTIMAGES)
-  {  
-    feature.MarkerGeneration(marker_pub, state_server.cam_states);
-    feature.VisualizePatch(cam_state, cam_state_id, cam0, photo_r, ss);
-  }
 
   return;
 }
@@ -1455,7 +1366,7 @@ void MsckfVio::PhotometricFeatureJacobian(
         state_server.cam_states.begin(), cam_state_iter);
 
     // Stack the Jacobians.
-    H_xi.block(stack_cntr, 0, H_xl.rows(), H_xl.cols()) = H_xl;
+    H_xi.block(stack_cntr, 21+cam_state_cntr*7, H_xl.rows(), H_xl.cols()) = H_xl;
     H_yi.block(stack_cntr, 0, H_yl.rows(), H_yl.cols()) = H_yl;
     r_i.segment(stack_cntr, N*N) = r_l;
     stack_cntr += N*N;
@@ -1500,8 +1411,7 @@ void MsckfVio::PhotometricFeatureJacobian(
 void MsckfVio::measurementJacobian(
     const StateIDType& cam_state_id,
     const FeatureIDType& feature_id,
-    Matrix<double, 4, 6>& H_x, Matrix<double, 4, 3>& H_f, Vector4d& r)
+    Matrix<double, 4, 6>& H_x, Matrix<double, 4, 3>& H_f, Vector4d& r) {
-{
 
   // Prepare all the required data.
   const CAMState& cam_state = state_server.cam_states[cam_state_id];
@@ -1540,8 +1450,6 @@ void MsckfVio::measurementJacobian(
   dz_dpc1(3, 2) = -p_c1(1) / (p_c1(2)*p_c1(2));
 
   Matrix<double, 3, 6> dpc0_dxc = Matrix<double, 3, 6>::Zero();
-  
-  // original jacobi
   dpc0_dxc.leftCols(3) = skewSymmetric(p_c0);
   dpc0_dxc.rightCols(3) = -R_w_c0;
 
@@ -1555,6 +1463,17 @@ void MsckfVio::measurementJacobian(
   H_x = dz_dpc0*dpc0_dxc + dz_dpc1*dpc1_dxc;
   H_f = dz_dpc0*dpc0_dpg + dz_dpc1*dpc1_dpg;
 
+  // Modifty the measurement Jacobian to ensure
+  // observability constrain.
+  Matrix<double, 4, 6> A = H_x;
+  Matrix<double, 6, 1> u = Matrix<double, 6, 1>::Zero();
+  u.block<3, 1>(0, 0) = quaternionToRotation(
+      cam_state.orientation_null) * IMUState::gravity;
+  u.block<3, 1>(3, 0) = skewSymmetric(
+      p_w-cam_state.position_null) * IMUState::gravity;
+  H_x = A - A*u*(u.transpose()*u).inverse()*u.transpose();
+  H_f = -H_x.block<4, 3>(0, 3);
+
   // Compute the residual.
   r = z - Vector4d(p_c0(0)/p_c0(2), p_c0(1)/p_c0(2),
       p_c1(0)/p_c1(2), p_c1(1)/p_c1(2));
@@ -1562,6 +1481,7 @@ void MsckfVio::measurementJacobian(
   return;
 }
 
+
 void MsckfVio::featureJacobian(
     const FeatureIDType& feature_id,
     const std::vector<StateIDType>& cam_state_ids,
@@ -1853,6 +1773,12 @@ void MsckfVio::removeLostFeatures() {
     else
       featureJacobian(feature.id, cam_state_ids, H_xj, r_j);
 
+    cout << "\n" << endl;
+    cout << "H_xj: \n" << H_xj << endl;
+    cout << "res: \n" << endl;
+    cout << r_j << endl; 
+    
+
     if (gatingTest(H_xj, r_j, cam_state_ids.size()-1)) {
       H_x.block(stack_cntr, 0, H_xj.rows(), H_xj.cols()) = H_xj;
       r.segment(stack_cntr, r_j.rows()) = r_j;
@@ -2015,6 +1941,12 @@ void MsckfVio::pruneCamStateBuffer() {
     else
       featureJacobian(feature.id, involved_cam_state_ids, H_xj, r_j);
 
+    cout << "\n" << endl;
+    cout << "H_xj: \n" << H_xj << endl;
+    cout << "res: \n" << endl;
+    cout << r_j << endl; 
+    
+    
     if (gatingTest(H_xj, r_j, involved_cam_state_ids.size())) {
       H_x.block(stack_cntr, 0, H_xj.rows(), H_xj.cols()) = H_xj;
       r.segment(stack_cntr, r_j.rows()) = r_j;