gtsam/matlab/+gtsam/points2DTrackStereo.m

72 lines
2.3 KiB
Matlab

function pts2dTracksStereo = points2DTrackStereo(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);
stereoNoise = noiseModel.Isotropic.Sigma(3,1);
cameraPosesNum = length(cameraPoses);
%% add measurements and initial camera & points values
pointsNum = 0;
cylinderNum = length(cylinders);
for i = 1:cylinderNum
pointsNum = pointsNum + length(cylinders{i}.Points);
end
pts3d = cell(cameraPosesNum, 1);
initialEstimate = Values;
initialized = false;
for i = 1:cameraPosesNum
pts3d{i} = cylinderSampleProjectionStereo(K, cameraPoses{i}, imageSize, cylinders);
if ~initialized
graph.add(PriorFactorPose3(symbol('x', 1), cameraPoses{i}, posePriorNoise));
initialized = true;
end
measurementNum = length(pts3d{i}.Z);
for j = 1:measurementNum
graph.add(GenericStereoFactor3D(StereoPoint2(pts3d{i}.Z{j}.uL, pts3d{i}.Z{j}.uR, pts3d{i}.Z{j}.v), ...
stereoNoise, symbol('x', i), symbol('p', pts3d{i}.overallIdx{j}), K));
end
end
%% initialize cameras and points close to ground truth
for i = 1:cameraPosesNum
pose_i = cameraPoses{i}.retract(0.1*randn(6,1));
initialEstimate.insert(symbol('x', i), pose_i);
end
ptsIdx = 0;
for i = 1:length(cylinders)
for j = 1:length(cylinders{i}.Points)
ptsIdx = ptsIdx + 1;
point_j = cylinders{i}.Points{j}.retract(0.1*randn(3,1));
initialEstimate.insert(symbol('p', ptsIdx), point_j);
end
end
%% Print the graph
graph.print(sprintf('\nFactor graph:\n'));
marginals = Marginals(graph, initialEstimate);
%% get all the 2d points track information
% currently throws the Indeterminant linear system exception
for k = 1:cameraPosesNum
pts2dTracksStereo.pt3d{ptx} = pts3d{k}.data{idx};
pts2dTracksStereo.Z{ptx} = pts3d{k}.Z{idx};
pts2dTracksStereo.cov{ptx} = marginals.marginalCovariance(symbol('p',pts3d{k}.overallIdx{visiblePointIdx}));
end
end