gtsam/matlab/+gtsam/points2DTrackMonocular.m

114 lines
3.5 KiB
Matlab

function pts2dTracksMono = points2DTrackMonocular(K, cameraPoses, imageSize, cylinders)
% Assess how accurately we can reconstruct points from a particular monocular camera setup.
% After creation of the factor graph for each track, linearize it around ground truth.
% There is no optimization
% @author: Zhaoyang Lv
import gtsam.*
%% create graph
graph = NonlinearFactorGraph;
%% create the noise factors
poseNoiseSigmas = [0.001 0.001 0.001 0.1 0.1 0.1]';
posePriorNoise = noiseModel.Diagonal.Sigmas(poseNoiseSigmas);
measurementNoiseSigma = 1.0;
measurementNoise = noiseModel.Isotropic.Sigma(2, measurementNoiseSigma);
cameraPosesNum = length(cameraPoses);
%% add measurements and initial camera & points values
pointsNum = 0;
cylinderNum = length(cylinders);
points3d = cell(0);
for i = 1:cylinderNum
cylinderPointsNum = length(cylinders{i}.Points);
pointsNum = pointsNum + cylinderPointsNum;
for j = 1:cylinderPointsNum
points3d{end+1}.data = cylinders{i}.Points{j};
points3d{end}.Z = cell(0);
points3d{end}.camConstraintIdx = cell(0);
points3d{end}.added = cell(0);
points3d{end}.visiblity = false;
points3d{end}.cov = cell(cameraPosesNum);
end
end
graph.add(PriorFactorPose3(symbol('x', 1), cameraPoses{1}, posePriorNoise));
%% initialize graph and values
initialEstimate = Values;
for i = 1:pointsNum
point_j = points3d{i}.data.retract(0.1*randn(3,1));
initialEstimate.insert(symbol('p', i), point_j);
end
pts3d = cell(cameraPosesNum, 1);
cameraPosesCov = cell(cameraPosesNum, 1);
marginals = Values;
for i = 1:cameraPosesNum
cameraPose = cameraPoses{i};
pts3d{i} = cylinderSampleProjection(K, cameraPose, imageSize, cylinders);
measurementNum = length(pts3d{i}.Z);
for j = 1:measurementNum
index = pts3d{i}.overallIdx{j};
points3d{index}.Z{end+1} = pts3d{i}.Z{j};
points3d{index}.camConstraintIdx{end+1} = i;
points3d{index}.added{end+1} = false;
if length(points3d{index}.Z) < 2
continue;
else
for k = 1:length(points3d{index}.Z)
if ~points3d{index}.added{k}
graph.add(GenericProjectionFactorCal3_S2(points3d{index}.Z{k}, ...
measurementNoise, symbol('x', points3d{index}.camConstraintIdx{k}), ...
symbol('p', index), K) );
points3d{index}.added{k} = true;
end
end
end
points3d{index}.visiblity = true;
end
pose_i = cameraPoses{i}.retract(0.1*randn(6,1));
initialEstimate.insert(symbol('x', i), pose_i);
marginals = Marginals(graph, initialEstimate);
for j = 1:pointsNum
if points3d{j}.visiblity
points3d{j}.cov{i} = marginals.marginalCovariance(symbol('p',j));
end
end
cameraPosesCov{i} = marginals.marginalCovariance(symbol('x',i));
end
%% Print the graph
graph.print(sprintf('\nFactor graph:\n'));
%% Plot the result
plotFlyingResults(points3d, cameraPoses, cameraPosesCov, cylinders, options);
%% get all the points track information
for i = 1:pointsNum
if ~points3d{i}.visiblity
continue;
end
pts2dTracksMono.pt3d{end+1} = points3d{i}.data;
pts2dTracksMono.Z{end+1} = points3d{i}.Z;
if length(points3d{i}.Z) == 1
%pts2dTracksMono.cov{i} singular matrix
else
pts2dTracksMono.cov{end+1} = marginals.marginalCovariance(symbol('p', i));
end
end
end