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Open Source Computer Vision Library
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630 lines
16 KiB
630 lines
16 KiB
#include <iostream> |
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#include "precomp.hpp" |
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#include "epnp.h" |
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namespace cv |
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{ |
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epnp::epnp(const Mat& cameraMatrix, const Mat& opoints, const Mat& ipoints) |
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{ |
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if (cameraMatrix.depth() == CV_32F) |
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init_camera_parameters<float>(cameraMatrix); |
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else |
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init_camera_parameters<double>(cameraMatrix); |
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number_of_correspondences = std::max(opoints.checkVector(3, CV_32F), opoints.checkVector(3, CV_64F)); |
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pws.resize(3 * number_of_correspondences); |
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us.resize(2 * number_of_correspondences); |
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if (opoints.depth() == ipoints.depth()) |
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{ |
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if (opoints.depth() == CV_32F) |
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init_points<Point3f,Point2f>(opoints, ipoints); |
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else |
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init_points<Point3d,Point2d>(opoints, ipoints); |
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} |
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else if (opoints.depth() == CV_32F) |
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init_points<Point3f,Point2d>(opoints, ipoints); |
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else |
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init_points<Point3d,Point2f>(opoints, ipoints); |
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alphas.resize(4 * number_of_correspondences); |
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pcs.resize(3 * number_of_correspondences); |
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max_nr = 0; |
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A1 = NULL; |
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A2 = NULL; |
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} |
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epnp::~epnp() |
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{ |
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if (A1) |
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delete[] A1; |
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if (A2) |
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delete[] A2; |
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} |
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void epnp::choose_control_points(void) |
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{ |
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// Take C0 as the reference points centroid: |
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cws[0][0] = cws[0][1] = cws[0][2] = 0; |
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for(int i = 0; i < number_of_correspondences; i++) |
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for(int j = 0; j < 3; j++) |
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cws[0][j] += pws[3 * i + j]; |
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for(int j = 0; j < 3; j++) |
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cws[0][j] /= number_of_correspondences; |
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// Take C1, C2, and C3 from PCA on the reference points: |
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CvMat * PW0 = cvCreateMat(number_of_correspondences, 3, CV_64F); |
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double pw0tpw0[3 * 3], dc[3] = {0}, uct[3 * 3] = {0}; |
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CvMat PW0tPW0 = cvMat(3, 3, CV_64F, pw0tpw0); |
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CvMat DC = cvMat(3, 1, CV_64F, dc); |
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CvMat UCt = cvMat(3, 3, CV_64F, uct); |
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for(int i = 0; i < number_of_correspondences; i++) |
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for(int j = 0; j < 3; j++) |
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PW0->data.db[3 * i + j] = pws[3 * i + j] - cws[0][j]; |
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cvMulTransposed(PW0, &PW0tPW0, 1); |
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cvSVD(&PW0tPW0, &DC, &UCt, 0, CV_SVD_MODIFY_A | CV_SVD_U_T); |
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cvReleaseMat(&PW0); |
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for(int i = 1; i < 4; i++) { |
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double k = sqrt(dc[i - 1] / number_of_correspondences); |
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for(int j = 0; j < 3; j++) |
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cws[i][j] = cws[0][j] + k * uct[3 * (i - 1) + j]; |
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} |
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} |
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void epnp::compute_barycentric_coordinates(void) |
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{ |
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double cc[3 * 3], cc_inv[3 * 3]; |
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CvMat CC = cvMat(3, 3, CV_64F, cc); |
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CvMat CC_inv = cvMat(3, 3, CV_64F, cc_inv); |
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for(int i = 0; i < 3; i++) |
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for(int j = 1; j < 4; j++) |
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cc[3 * i + j - 1] = cws[j][i] - cws[0][i]; |
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cvInvert(&CC, &CC_inv, CV_SVD); |
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double * ci = cc_inv; |
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for(int i = 0; i < number_of_correspondences; i++) { |
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double * pi = &pws[0] + 3 * i; |
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double * a = &alphas[0] + 4 * i; |
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for(int j = 0; j < 3; j++) |
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a[1 + j] = |
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ci[3 * j ] * (pi[0] - cws[0][0]) + |
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ci[3 * j + 1] * (pi[1] - cws[0][1]) + |
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ci[3 * j + 2] * (pi[2] - cws[0][2]); |
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a[0] = 1.0f - a[1] - a[2] - a[3]; |
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} |
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} |
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void epnp::fill_M(CvMat * M, |
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const int row, const double * as, const double u, const double v) |
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{ |
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double * M1 = M->data.db + row * 12; |
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double * M2 = M1 + 12; |
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for(int i = 0; i < 4; i++) { |
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M1[3 * i ] = as[i] * fu; |
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M1[3 * i + 1] = 0.0; |
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M1[3 * i + 2] = as[i] * (uc - u); |
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M2[3 * i ] = 0.0; |
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M2[3 * i + 1] = as[i] * fv; |
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M2[3 * i + 2] = as[i] * (vc - v); |
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} |
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} |
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void epnp::compute_ccs(const double * betas, const double * ut) |
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{ |
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for(int i = 0; i < 4; i++) |
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ccs[i][0] = ccs[i][1] = ccs[i][2] = 0.0f; |
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for(int i = 0; i < 4; i++) { |
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const double * v = ut + 12 * (11 - i); |
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for(int j = 0; j < 4; j++) |
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for(int k = 0; k < 3; k++) |
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ccs[j][k] += betas[i] * v[3 * j + k]; |
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} |
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} |
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void epnp::compute_pcs(void) |
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{ |
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for(int i = 0; i < number_of_correspondences; i++) { |
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double * a = &alphas[0] + 4 * i; |
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double * pc = &pcs[0] + 3 * i; |
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for(int j = 0; j < 3; j++) |
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pc[j] = a[0] * ccs[0][j] + a[1] * ccs[1][j] + a[2] * ccs[2][j] + a[3] * ccs[3][j]; |
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} |
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} |
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void epnp::compute_pose(Mat& R, Mat& t) |
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{ |
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choose_control_points(); |
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compute_barycentric_coordinates(); |
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CvMat * M = cvCreateMat(2 * number_of_correspondences, 12, CV_64F); |
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for(int i = 0; i < number_of_correspondences; i++) |
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fill_M(M, 2 * i, &alphas[0] + 4 * i, us[2 * i], us[2 * i + 1]); |
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double mtm[12 * 12], d[12], ut[12 * 12]; |
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CvMat MtM = cvMat(12, 12, CV_64F, mtm); |
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CvMat D = cvMat(12, 1, CV_64F, d); |
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CvMat Ut = cvMat(12, 12, CV_64F, ut); |
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cvMulTransposed(M, &MtM, 1); |
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cvSVD(&MtM, &D, &Ut, 0, CV_SVD_MODIFY_A | CV_SVD_U_T); |
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cvReleaseMat(&M); |
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double l_6x10[6 * 10], rho[6]; |
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CvMat L_6x10 = cvMat(6, 10, CV_64F, l_6x10); |
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CvMat Rho = cvMat(6, 1, CV_64F, rho); |
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compute_L_6x10(ut, l_6x10); |
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compute_rho(rho); |
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double Betas[4][4], rep_errors[4]; |
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double Rs[4][3][3], ts[4][3]; |
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find_betas_approx_1(&L_6x10, &Rho, Betas[1]); |
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gauss_newton(&L_6x10, &Rho, Betas[1]); |
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rep_errors[1] = compute_R_and_t(ut, Betas[1], Rs[1], ts[1]); |
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find_betas_approx_2(&L_6x10, &Rho, Betas[2]); |
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gauss_newton(&L_6x10, &Rho, Betas[2]); |
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rep_errors[2] = compute_R_and_t(ut, Betas[2], Rs[2], ts[2]); |
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find_betas_approx_3(&L_6x10, &Rho, Betas[3]); |
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gauss_newton(&L_6x10, &Rho, Betas[3]); |
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rep_errors[3] = compute_R_and_t(ut, Betas[3], Rs[3], ts[3]); |
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int N = 1; |
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if (rep_errors[2] < rep_errors[1]) N = 2; |
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if (rep_errors[3] < rep_errors[N]) N = 3; |
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Mat(3, 1, CV_64F, ts[N]).copyTo(t); |
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Mat(3, 3, CV_64F, Rs[N]).copyTo(R); |
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} |
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void epnp::copy_R_and_t(const double R_src[3][3], const double t_src[3], |
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double R_dst[3][3], double t_dst[3]) |
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{ |
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for(int i = 0; i < 3; i++) { |
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for(int j = 0; j < 3; j++) |
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R_dst[i][j] = R_src[i][j]; |
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t_dst[i] = t_src[i]; |
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} |
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} |
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double epnp::dist2(const double * p1, const double * p2) |
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{ |
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return |
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(p1[0] - p2[0]) * (p1[0] - p2[0]) + |
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(p1[1] - p2[1]) * (p1[1] - p2[1]) + |
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(p1[2] - p2[2]) * (p1[2] - p2[2]); |
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} |
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double epnp::dot(const double * v1, const double * v2) |
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{ |
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return v1[0] * v2[0] + v1[1] * v2[1] + v1[2] * v2[2]; |
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} |
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void epnp::estimate_R_and_t(double R[3][3], double t[3]) |
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{ |
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double pc0[3], pw0[3]; |
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pc0[0] = pc0[1] = pc0[2] = 0.0; |
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pw0[0] = pw0[1] = pw0[2] = 0.0; |
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for(int i = 0; i < number_of_correspondences; i++) { |
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const double * pc = &pcs[3 * i]; |
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const double * pw = &pws[3 * i]; |
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for(int j = 0; j < 3; j++) { |
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pc0[j] += pc[j]; |
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pw0[j] += pw[j]; |
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} |
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} |
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for(int j = 0; j < 3; j++) { |
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pc0[j] /= number_of_correspondences; |
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pw0[j] /= number_of_correspondences; |
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} |
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double abt[3 * 3] = {0}, abt_d[3], abt_u[3 * 3], abt_v[3 * 3]; |
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CvMat ABt = cvMat(3, 3, CV_64F, abt); |
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CvMat ABt_D = cvMat(3, 1, CV_64F, abt_d); |
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CvMat ABt_U = cvMat(3, 3, CV_64F, abt_u); |
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CvMat ABt_V = cvMat(3, 3, CV_64F, abt_v); |
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cvSetZero(&ABt); |
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for(int i = 0; i < number_of_correspondences; i++) { |
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double * pc = &pcs[3 * i]; |
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double * pw = &pws[3 * i]; |
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for(int j = 0; j < 3; j++) { |
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abt[3 * j ] += (pc[j] - pc0[j]) * (pw[0] - pw0[0]); |
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abt[3 * j + 1] += (pc[j] - pc0[j]) * (pw[1] - pw0[1]); |
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abt[3 * j + 2] += (pc[j] - pc0[j]) * (pw[2] - pw0[2]); |
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} |
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} |
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cvSVD(&ABt, &ABt_D, &ABt_U, &ABt_V, CV_SVD_MODIFY_A); |
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for(int i = 0; i < 3; i++) |
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for(int j = 0; j < 3; j++) |
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R[i][j] = dot(abt_u + 3 * i, abt_v + 3 * j); |
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const double det = |
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R[0][0] * R[1][1] * R[2][2] + R[0][1] * R[1][2] * R[2][0] + R[0][2] * R[1][0] * R[2][1] - |
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R[0][2] * R[1][1] * R[2][0] - R[0][1] * R[1][0] * R[2][2] - R[0][0] * R[1][2] * R[2][1]; |
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if (det < 0) { |
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R[2][0] = -R[2][0]; |
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R[2][1] = -R[2][1]; |
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R[2][2] = -R[2][2]; |
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} |
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t[0] = pc0[0] - dot(R[0], pw0); |
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t[1] = pc0[1] - dot(R[1], pw0); |
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t[2] = pc0[2] - dot(R[2], pw0); |
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} |
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void epnp::solve_for_sign(void) |
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{ |
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if (pcs[2] < 0.0) { |
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for(int i = 0; i < 4; i++) |
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for(int j = 0; j < 3; j++) |
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ccs[i][j] = -ccs[i][j]; |
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for(int i = 0; i < number_of_correspondences; i++) { |
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pcs[3 * i ] = -pcs[3 * i]; |
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pcs[3 * i + 1] = -pcs[3 * i + 1]; |
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pcs[3 * i + 2] = -pcs[3 * i + 2]; |
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} |
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} |
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} |
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double epnp::compute_R_and_t(const double * ut, const double * betas, |
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double R[3][3], double t[3]) |
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{ |
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compute_ccs(betas, ut); |
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compute_pcs(); |
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solve_for_sign(); |
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estimate_R_and_t(R, t); |
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return reprojection_error(R, t); |
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} |
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double epnp::reprojection_error(const double R[3][3], const double t[3]) |
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{ |
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double sum2 = 0.0; |
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for(int i = 0; i < number_of_correspondences; i++) { |
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double * pw = &pws[3 * i]; |
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double Xc = dot(R[0], pw) + t[0]; |
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double Yc = dot(R[1], pw) + t[1]; |
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double inv_Zc = 1.0 / (dot(R[2], pw) + t[2]); |
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double ue = uc + fu * Xc * inv_Zc; |
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double ve = vc + fv * Yc * inv_Zc; |
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double u = us[2 * i], v = us[2 * i + 1]; |
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sum2 += sqrt( (u - ue) * (u - ue) + (v - ve) * (v - ve) ); |
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} |
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return sum2 / number_of_correspondences; |
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} |
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// betas10 = [B11 B12 B22 B13 B23 B33 B14 B24 B34 B44] |
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// betas_approx_1 = [B11 B12 B13 B14] |
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void epnp::find_betas_approx_1(const CvMat * L_6x10, const CvMat * Rho, |
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double * betas) |
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{ |
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double l_6x4[6 * 4], b4[4] = {0}; |
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CvMat L_6x4 = cvMat(6, 4, CV_64F, l_6x4); |
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CvMat B4 = cvMat(4, 1, CV_64F, b4); |
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for(int i = 0; i < 6; i++) { |
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cvmSet(&L_6x4, i, 0, cvmGet(L_6x10, i, 0)); |
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cvmSet(&L_6x4, i, 1, cvmGet(L_6x10, i, 1)); |
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cvmSet(&L_6x4, i, 2, cvmGet(L_6x10, i, 3)); |
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cvmSet(&L_6x4, i, 3, cvmGet(L_6x10, i, 6)); |
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} |
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cvSolve(&L_6x4, Rho, &B4, CV_SVD); |
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if (b4[0] < 0) { |
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betas[0] = sqrt(-b4[0]); |
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betas[1] = -b4[1] / betas[0]; |
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betas[2] = -b4[2] / betas[0]; |
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betas[3] = -b4[3] / betas[0]; |
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} else { |
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betas[0] = sqrt(b4[0]); |
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betas[1] = b4[1] / betas[0]; |
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betas[2] = b4[2] / betas[0]; |
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betas[3] = b4[3] / betas[0]; |
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} |
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} |
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// betas10 = [B11 B12 B22 B13 B23 B33 B14 B24 B34 B44] |
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// betas_approx_2 = [B11 B12 B22 ] |
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void epnp::find_betas_approx_2(const CvMat * L_6x10, const CvMat * Rho, |
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double * betas) |
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{ |
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double l_6x3[6 * 3], b3[3] = {0}; |
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CvMat L_6x3 = cvMat(6, 3, CV_64F, l_6x3); |
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CvMat B3 = cvMat(3, 1, CV_64F, b3); |
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for(int i = 0; i < 6; i++) { |
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cvmSet(&L_6x3, i, 0, cvmGet(L_6x10, i, 0)); |
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cvmSet(&L_6x3, i, 1, cvmGet(L_6x10, i, 1)); |
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cvmSet(&L_6x3, i, 2, cvmGet(L_6x10, i, 2)); |
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} |
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cvSolve(&L_6x3, Rho, &B3, CV_SVD); |
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if (b3[0] < 0) { |
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betas[0] = sqrt(-b3[0]); |
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betas[1] = (b3[2] < 0) ? sqrt(-b3[2]) : 0.0; |
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} else { |
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betas[0] = sqrt(b3[0]); |
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betas[1] = (b3[2] > 0) ? sqrt(b3[2]) : 0.0; |
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} |
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if (b3[1] < 0) betas[0] = -betas[0]; |
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betas[2] = 0.0; |
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betas[3] = 0.0; |
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} |
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// betas10 = [B11 B12 B22 B13 B23 B33 B14 B24 B34 B44] |
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// betas_approx_3 = [B11 B12 B22 B13 B23 ] |
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void epnp::find_betas_approx_3(const CvMat * L_6x10, const CvMat * Rho, |
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double * betas) |
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{ |
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double l_6x5[6 * 5], b5[5] = {0}; |
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CvMat L_6x5 = cvMat(6, 5, CV_64F, l_6x5); |
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CvMat B5 = cvMat(5, 1, CV_64F, b5); |
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for(int i = 0; i < 6; i++) { |
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cvmSet(&L_6x5, i, 0, cvmGet(L_6x10, i, 0)); |
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cvmSet(&L_6x5, i, 1, cvmGet(L_6x10, i, 1)); |
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cvmSet(&L_6x5, i, 2, cvmGet(L_6x10, i, 2)); |
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cvmSet(&L_6x5, i, 3, cvmGet(L_6x10, i, 3)); |
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cvmSet(&L_6x5, i, 4, cvmGet(L_6x10, i, 4)); |
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} |
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cvSolve(&L_6x5, Rho, &B5, CV_SVD); |
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if (b5[0] < 0) { |
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betas[0] = sqrt(-b5[0]); |
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betas[1] = (b5[2] < 0) ? sqrt(-b5[2]) : 0.0; |
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} else { |
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betas[0] = sqrt(b5[0]); |
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betas[1] = (b5[2] > 0) ? sqrt(b5[2]) : 0.0; |
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} |
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if (b5[1] < 0) betas[0] = -betas[0]; |
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betas[2] = b5[3] / betas[0]; |
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betas[3] = 0.0; |
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} |
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void epnp::compute_L_6x10(const double * ut, double * l_6x10) |
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{ |
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const double * v[4]; |
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v[0] = ut + 12 * 11; |
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v[1] = ut + 12 * 10; |
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v[2] = ut + 12 * 9; |
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v[3] = ut + 12 * 8; |
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double dv[4][6][3]; |
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for(int i = 0; i < 4; i++) { |
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int a = 0, b = 1; |
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for(int j = 0; j < 6; j++) { |
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dv[i][j][0] = v[i][3 * a ] - v[i][3 * b]; |
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dv[i][j][1] = v[i][3 * a + 1] - v[i][3 * b + 1]; |
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dv[i][j][2] = v[i][3 * a + 2] - v[i][3 * b + 2]; |
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b++; |
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if (b > 3) { |
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a++; |
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b = a + 1; |
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} |
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} |
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} |
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for(int i = 0; i < 6; i++) { |
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double * row = l_6x10 + 10 * i; |
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|
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row[0] = dot(dv[0][i], dv[0][i]); |
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row[1] = 2.0f * dot(dv[0][i], dv[1][i]); |
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row[2] = dot(dv[1][i], dv[1][i]); |
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row[3] = 2.0f * dot(dv[0][i], dv[2][i]); |
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row[4] = 2.0f * dot(dv[1][i], dv[2][i]); |
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row[5] = dot(dv[2][i], dv[2][i]); |
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row[6] = 2.0f * dot(dv[0][i], dv[3][i]); |
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row[7] = 2.0f * dot(dv[1][i], dv[3][i]); |
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row[8] = 2.0f * dot(dv[2][i], dv[3][i]); |
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row[9] = dot(dv[3][i], dv[3][i]); |
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} |
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} |
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|
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void epnp::compute_rho(double * rho) |
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{ |
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rho[0] = dist2(cws[0], cws[1]); |
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rho[1] = dist2(cws[0], cws[2]); |
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rho[2] = dist2(cws[0], cws[3]); |
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rho[3] = dist2(cws[1], cws[2]); |
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rho[4] = dist2(cws[1], cws[3]); |
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rho[5] = dist2(cws[2], cws[3]); |
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} |
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|
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void epnp::compute_A_and_b_gauss_newton(const double * l_6x10, const double * rho, |
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const double betas[4], CvMat * A, CvMat * b) |
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{ |
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for(int i = 0; i < 6; i++) { |
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const double * rowL = l_6x10 + i * 10; |
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double * rowA = A->data.db + i * 4; |
|
|
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rowA[0] = 2 * rowL[0] * betas[0] + rowL[1] * betas[1] + rowL[3] * betas[2] + rowL[6] * betas[3]; |
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rowA[1] = rowL[1] * betas[0] + 2 * rowL[2] * betas[1] + rowL[4] * betas[2] + rowL[7] * betas[3]; |
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rowA[2] = rowL[3] * betas[0] + rowL[4] * betas[1] + 2 * rowL[5] * betas[2] + rowL[8] * betas[3]; |
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rowA[3] = rowL[6] * betas[0] + rowL[7] * betas[1] + rowL[8] * betas[2] + 2 * rowL[9] * betas[3]; |
|
|
|
cvmSet(b, i, 0, rho[i] - |
|
( |
|
rowL[0] * betas[0] * betas[0] + |
|
rowL[1] * betas[0] * betas[1] + |
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rowL[2] * betas[1] * betas[1] + |
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rowL[3] * betas[0] * betas[2] + |
|
rowL[4] * betas[1] * betas[2] + |
|
rowL[5] * betas[2] * betas[2] + |
|
rowL[6] * betas[0] * betas[3] + |
|
rowL[7] * betas[1] * betas[3] + |
|
rowL[8] * betas[2] * betas[3] + |
|
rowL[9] * betas[3] * betas[3] |
|
)); |
|
} |
|
} |
|
|
|
void epnp::gauss_newton(const CvMat * L_6x10, const CvMat * Rho, double betas[4]) |
|
{ |
|
const int iterations_number = 5; |
|
|
|
double a[6*4], b[6], x[4] = {0}; |
|
CvMat A = cvMat(6, 4, CV_64F, a); |
|
CvMat B = cvMat(6, 1, CV_64F, b); |
|
CvMat X = cvMat(4, 1, CV_64F, x); |
|
|
|
for(int k = 0; k < iterations_number; k++) |
|
{ |
|
compute_A_and_b_gauss_newton(L_6x10->data.db, Rho->data.db, |
|
betas, &A, &B); |
|
qr_solve(&A, &B, &X); |
|
for(int i = 0; i < 4; i++) |
|
betas[i] += x[i]; |
|
} |
|
} |
|
|
|
void epnp::qr_solve(CvMat * A, CvMat * b, CvMat * X) |
|
{ |
|
const int nr = A->rows; |
|
const int nc = A->cols; |
|
if (nc <= 0 || nr <= 0) |
|
return; |
|
|
|
if (max_nr != 0 && max_nr < nr) |
|
{ |
|
delete [] A1; |
|
delete [] A2; |
|
} |
|
if (max_nr < nr) |
|
{ |
|
max_nr = nr; |
|
A1 = new double[nr]; |
|
A2 = new double[nr]; |
|
} |
|
|
|
double * pA = A->data.db, * ppAkk = pA; |
|
for(int k = 0; k < nc; k++) |
|
{ |
|
double * ppAik1 = ppAkk, eta = fabs(*ppAik1); |
|
for(int i = k + 1; i < nr; i++) |
|
{ |
|
double elt = fabs(*ppAik1); |
|
if (eta < elt) eta = elt; |
|
ppAik1 += nc; |
|
} |
|
if (eta == 0) |
|
{ |
|
A1[k] = A2[k] = 0.0; |
|
//cerr << "God damnit, A is singular, this shouldn't happen." << endl; |
|
return; |
|
} |
|
else |
|
{ |
|
double * ppAik2 = ppAkk, sum2 = 0.0, inv_eta = 1. / eta; |
|
for(int i = k; i < nr; i++) |
|
{ |
|
*ppAik2 *= inv_eta; |
|
sum2 += *ppAik2 * *ppAik2; |
|
ppAik2 += nc; |
|
} |
|
double sigma = sqrt(sum2); |
|
if (*ppAkk < 0) |
|
sigma = -sigma; |
|
*ppAkk += sigma; |
|
A1[k] = sigma * *ppAkk; |
|
A2[k] = -eta * sigma; |
|
for(int j = k + 1; j < nc; j++) |
|
{ |
|
double * ppAik = ppAkk, sum = 0; |
|
for(int i = k; i < nr; i++) |
|
{ |
|
sum += *ppAik * ppAik[j - k]; |
|
ppAik += nc; |
|
} |
|
double tau = sum / A1[k]; |
|
ppAik = ppAkk; |
|
for(int i = k; i < nr; i++) |
|
{ |
|
ppAik[j - k] -= tau * *ppAik; |
|
ppAik += nc; |
|
} |
|
} |
|
} |
|
ppAkk += nc + 1; |
|
} |
|
|
|
// b <- Qt b |
|
double * ppAjj = pA, * pb = b->data.db; |
|
for(int j = 0; j < nc; j++) |
|
{ |
|
double * ppAij = ppAjj, tau = 0; |
|
for(int i = j; i < nr; i++) |
|
{ |
|
tau += *ppAij * pb[i]; |
|
ppAij += nc; |
|
} |
|
tau /= A1[j]; |
|
ppAij = ppAjj; |
|
for(int i = j; i < nr; i++) |
|
{ |
|
pb[i] -= tau * *ppAij; |
|
ppAij += nc; |
|
} |
|
ppAjj += nc + 1; |
|
} |
|
|
|
// X = R-1 b |
|
double * pX = X->data.db; |
|
pX[nc - 1] = pb[nc - 1] / A2[nc - 1]; |
|
for(int i = nc - 2; i >= 0; i--) |
|
{ |
|
double * ppAij = pA + i * nc + (i + 1), sum = 0; |
|
|
|
for(int j = i + 1; j < nc; j++) |
|
{ |
|
sum += *ppAij * pX[j]; |
|
ppAij++; |
|
} |
|
pX[i] = (pb[i] - sum) / A2[i]; |
|
} |
|
} |
|
|
|
}
|
|
|