File: create2D2DOmniExperiment.m

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function [v1, v2, t, R ] = create2D2DOmniExperiment( pt_number, cam_number, noise, outlier_fraction )

%% generate the camera system

cam_distance = 1.0;

%% set a regular camera system with 2 or 4 cameras here
if cam_number == 2
  cam_offsets = [ cam_distance -cam_distance; 0.0 0.0; 0.0 0.0  ];
else
  cam_number = 4; % only two or 4 supported for this experiment
  cam_offsets = [ cam_distance 0.0 -cam_distance 0.0; 0.0 cam_distance 0.0 -cam_distance; 0.0 0.0 0.0 0.0 ];
end

%% generate random view-points

max_parallax = 2.0;
max_rotation = 0.5;

position1 = zeros(3,1);
rotation1 = eye(3);

position2 = max_parallax * 2.0 * (rand(3,1) - repmat(0.5,3,1));
rotation2 = generateBoundedR(max_rotation);

%% Generate random point-cloud

avg_depth_over_cam_distance = 10.0;
maxDepth = 5.0;

normalizedPoints = 2.0*(rand(3,pt_number)-repmat(0.5,3,pt_number));
points = maxDepth * normalizedPoints;

%% Now create the correspondences by looping through the cameras

focal_length = 800.0;

v1 = zeros(6,pt_number);
v2 = zeros(6,pt_number);
cam_correspondence = 1;
cam_correspondences = zeros(1,pt_number);

for i=1:pt_number
    
    cam_offset = cam_offsets(:,cam_correspondence);
    %cam_rotation = cam_rotations(:,(cam_correspondence-1)*3+1:(cam_correspondence-1)*3+3);
    
	%special: shift the point in the first frame along current camera axis, which guarantees homogeneous distribution
	temp = points(:,i) + avg_depth_over_cam_distance * cam_offset;
	points(:,i) = temp;
	
    body_point1 = rotation1' * (points(:,i)-position1);
    body_point2 = rotation2' * (points(:,i)-position2);
    
    % we actually omit the can rotation here by unrotating the bearing
    % vectors already
    bearingVector1 = body_point1 - cam_offset;
    bearingVector2 = body_point2 - cam_offset;
    bearingVector1_norm = norm(bearingVector1);
    bearingVector2_norm = norm(bearingVector2);
    bearingVector1 = bearingVector1/bearingVector1_norm;
    bearingVector2 = bearingVector2/bearingVector2_norm;
    
    % add noise to the bearing vectors here
    bearingVector1_noisy = addNoise(bearingVector1,focal_length,noise);
    bearingVector2_noisy = addNoise(bearingVector2,focal_length,noise);
    
    % store the normalized bearing vectors along with the cameras they are
    % being seen (we create correspondences that always originate from the
    % same camera, you can change this if you want)
    bearingVector1_norm = norm(bearingVector1_noisy);
    bearingVector2_norm = norm(bearingVector2_noisy);
    
    v1(:,i) = [bearingVector1_noisy./bearingVector1_norm; cam_offset];
    v2(:,i) = [bearingVector2_noisy./bearingVector2_norm; cam_offset];
    
    % change the camera correspondence
    cam_correspondences(1,i) = cam_correspondence;
    cam_correspondence = cam_correspondence + 1;
    if cam_correspondence > cam_number
        cam_correspondence = 1;
    end
end

%% Add outliers
number_outliers = floor(outlier_fraction*pt_number);

if number_outliers > 0
for i=1:number_outliers
    
    cam_correspondence = cam_correspondences(1,i);
    
    cam_offset = cam_offsets(:,cam_correspondence);
    %cam_rotation = cam_rotations(:,(cam_correspondence-1)*3+1:(cam_correspondence-1)*3+3);
    
    %generate random point
    normalizedPoint = 2.0*(rand(3,1)-repmat(0.5,3,1));
    point = maxDepth * normalizedPoint + avg_depth_over_cam_distance * cam_offset;
	
    
    body_point2 = rotation2' * (point-position2);
    
    % store the point (no need to add noise)
    bearingVector2 = body_point2 - cam_offset;
    
    % store the normalized bearing vectors along with the cameras they are
    % being seen (we create correspondences that always originate from the
    % same camera, you can change this if you want)
    bearingVector2_norm = norm(bearingVector2);
    
    v2(:,i) = [bearingVector2./bearingVector2_norm; cam_offset];
end
end

%% compute relative translation and rotation

R = rotation1' * rotation2;
t = rotation1' * (position2 - position1);