gtsam/matlab/examples/+support/VisualISAMInitialize.m

67 lines
2.3 KiB
Matlab

function [noiseModels,isam,result] = VisualISAMInitialize(data,truth,options)
% VisualInitialize: initialize visualSLAM::iSAM object and noise parameters
% Authors: Duy Nguyen Ta, Frank Dellaert and Alex Cunningham
%% Initialize iSAM
isam = visualSLAM.ISAM(options.reorderInterval);
%% Set Noise parameters
import gtsam.*
noiseModels.pose = noiseModel.Diagonal.Sigmas([0.001 0.001 0.001 0.1 0.1 0.1]');
%noiseModels.odometry = noiseModel.Diagonal.Sigmas([0.001 0.001 0.001 0.1 0.1 0.1]');
noiseModels.odometry = noiseModel.Diagonal.Sigmas([0.1 0.1 0.1 1.0 1.0 1.0]');
noiseModels.point = noiseModel.Isotropic.Sigma(3, 0.1);
noiseModels.measurement = noiseModel.Isotropic.Sigma(2, 1.0);
%% Add constraints/priors
% TODO: should not be from ground truth!
newFactors = visualSLAM.Graph;
initialEstimates = visualSLAM.Values;
for i=1:2
ii = symbol('x',i);
if i==1
if options.hardConstraint % add hard constraint
newFactors.addPoseConstraint(ii,truth.cameras{1}.pose);
else
newFactors.addPosePrior(ii,truth.cameras{i}.pose, noiseModels.pose);
end
end
initialEstimates.insertPose(ii,truth.cameras{i}.pose);
end
%% Add visual measurement factors from two first poses and initialize observed landmarks
for i=1:2
ii = symbol('x',i);
for k=1:length(data.Z{i})
j = data.J{i}{k};
jj = symbol('l',data.J{i}{k});
newFactors.addMeasurement(data.Z{i}{k}, noiseModels.measurement, ii, jj, data.K);
% TODO: initial estimates should not be from ground truth!
if ~initialEstimates.exists(jj)
initialEstimates.insertPoint(jj, truth.points{j});
end
if options.pointPriors % add point priors
newFactors.addPointPrior(jj, truth.points{j}, noiseModels.point);
end
end
end
%% Add odometry between frames 1 and 2
newFactors.addRelativePose(symbol('x',1), symbol('x',2), data.odometry{1}, noiseModels.odometry);
%% Update ISAM
if options.batchInitialization % Do a full optimize for first two poses
fullyOptimized = newFactors.optimize(initialEstimates,0);
isam.update(newFactors, fullyOptimized);
else
isam.update(newFactors, initialEstimates);
end
% figure(1);tic;
% t=toc; plot(frame_i,t,'r.'); tic
result = isam.estimate();
% t=toc; plot(frame_i,t,'g.');
if options.alwaysRelinearize % re-linearize
isam.reorder_relinearize();
end