% By Philip Torr 2002 % copyright Microsoft Corp. %this is a script to test the self calibration stuff %torr_test_calib_sc.m %main() %profile on clear all; m3 = 256; method = 'mapsac'; method = 'linear'; % % do we want the same result each time % randn('state',0) % rand('state',0) no_test = 1; for(i = 1:no_test) % [true_F,x1,y1,x2,y2,nx1,ny1,nx2,ny2] = ... % torr_gen_2view_matches(foc, no_matches, noise_sigma, translation_mult, translation_adder, ... % rotation_multplier, min_Z,Z_RAN,m3); [true_F,x1,y1,x2,y2,nx1,ny1,nx2,ny2,true_C,true_R,true_TX, true_E] = torr_gen_2view_matches; no_matches = length(nx1); %if we set this to one then the result should be the same as the groundtruth... no_noise = 1; if (no_noise) disp('just using noise free points'); nx1 = x1; nx2 = x2; ny1 = y1; ny2 = y2; end matches = [nx1,ny1,nx2,ny2]; perfect_matches = [x1,y1,x2,y2]; set_rank2 = 1; %first estimate F [f, e1, n_inliers,inlier_index,nF] = torr_estimateF( matches, m3, [], method, set_rank2); %now guess the camera calibration matrix CC = diag(ones(3,1),0); CC(3,3) = 1; %next self calibrate for focal length [focal_length, nE,CCC] = torr_self_calib_f(nF,CC); %now we have an Essential matrix we can establish the camera frame... [P1,P2,R,t,srot_axis,rot_angle,g] = torr_linear_EtoPX(nE,matches,CCC,m3); %next convert the 6 parameters of g to a fundamental matrix f2 = torr_g2F(g,CCC); disp('error before non-linear minimization') e = torr_errf2(f2, nx1,ny1,nx2,ny2, length(nx1), m3); norm(e) [g,f] = torr_nonlinG(g ,nx1,ny1,nx2,ny2, no_matches, m3, CCC) disp('error after') e2 = torr_errf2(f, nx1,ny1,nx2,ny2, length(nx1), m3); norm(e2) %the question now arises: how good is the fit? compare to groundtruth true_rot_axis = [true_R(3,2)-true_R(2,3), true_R(1,3) - true_R(3,1), true_R(2,1) - true_R(1,2)]'; true_rot_axis = true_rot_axis /norm(true_rot_axis); true_rot_angle = acos( (trace(true_R)-1)/2); true_t(1) = -true_TX(2,3); true_t(2) = true_TX(1,3); true_t(3) = -true_TX(1,2); true_t = true_t/norm(true_t); disp('true camera parameters') true_t true_rot_axis true_rot_angle true_C rot_axis = torr_sphere2unit([g(2) g(3)]); tt = torr_sphere2unit([g(5) g(6)]); rot_angle = g(4); CCC(3,3) = 1/g(1); disp('estimated camera parameters') tt rot_axis rot_angle CCC end