Bundle-Adjustment methods

Detailed Description

Collaboration diagram for Bundle-Adjustment methods:

Bundle-Adjustment methods
double VISION_IMPEXP	mrpt::vision::bundle_adj_full (const mrpt::vision::TSequenceFeatureObservations &observations, const mrpt::utils::TCamera &camera_params, mrpt::vision::TFramePosesVec &frame_poses, mrpt::vision::TLandmarkLocationsVec &landmark_points, const mrpt::utils::TParametersDouble &extra_params=mrpt::utils::TParametersDouble(), const mrpt::vision::TBundleAdjustmentFeedbackFunctor user_feedback=NULL)
	Sparse Levenberg-Marquart solution to bundle adjustment - optimizes all the camera frames & the landmark locations. More...

Bundle-Adjustment Auxiliary methods
void VISION_IMPEXP	mrpt::vision::ba_initial_estimate (const mrpt::vision::TSequenceFeatureObservations &observations, const mrpt::utils::TCamera &camera_params, mrpt::vision::TFramePosesVec &frame_poses, mrpt::vision::TLandmarkLocationsVec &landmark_points)
	Fills the frames & landmark points maps with an initial gross estimate from the sequence observations, so they can be fed to bundle adjustment methods. More...
double VISION_IMPEXP	mrpt::vision::reprojectionResiduals (const mrpt::vision::TSequenceFeatureObservations &observations, const mrpt::utils::TCamera &camera_params, const mrpt::vision::TFramePosesVec &frame_poses, const mrpt::vision::TLandmarkLocationsVec &landmark_points, std::vector< CArray< double, 2 > > &out_residuals, const bool frame_poses_are_inverse, const bool use_robust_kernel=true, const double kernel_param=3.0, std::vector< double > *out_kernel_1st_deriv=NULL)
	Compute reprojection error vector (used from within Bundle Adjustment methods, but can be used in general) See mrpt::vision::bundle_adj_full for a description of most parameters. More...
void VISION_IMPEXP	mrpt::vision::add_se3_deltas_to_frames (const mrpt::vision::TFramePosesVec &frame_poses, const mrpt::vector_double &delta, const size_t delta_first_idx, const size_t delta_num_vals, mrpt::vision::TFramePosesVec &new_frame_poses, const size_t num_fix_frames)
	For each pose in the vector frame_poses, adds a "delta" increment to the manifold, with the "delta" given in the se(3) Lie algebra: More...
void VISION_IMPEXP	mrpt::vision::add_3d_deltas_to_points (const mrpt::vision::TLandmarkLocationsVec &landmark_points, const mrpt::vector_double &delta, const size_t delta_first_idx, const size_t delta_num_vals, mrpt::vision::TLandmarkLocationsVec &new_landmark_points, const size_t num_fix_points)
	For each pose in the vector frame_poses, adds a "delta" increment to the manifold, with the "delta" given in the se(3) Lie algebra: More...
void VISION_IMPEXP	mrpt::vision::ba_initial_estimate (const mrpt::vision::TSequenceFeatureObservations &observations, const mrpt::utils::TCamera &camera_params, mrpt::vision::TFramePosesMap &frame_poses, mrpt::vision::TLandmarkLocationsMap &landmark_points)
double VISION_IMPEXP	mrpt::vision::reprojectionResiduals (const mrpt::vision::TSequenceFeatureObservations &observations, const mrpt::utils::TCamera &camera_params, const mrpt::vision::TFramePosesMap &frame_poses, const mrpt::vision::TLandmarkLocationsMap &landmark_points, std::vector< CArray< double, 2 > > &out_residuals, const bool frame_poses_are_inverse, const bool use_robust_kernel=true, const double kernel_param=3.0, std::vector< double > *out_kernel_1st_deriv=NULL)

Function Documentation

add_3d_deltas_to_points()

void VISION_IMPEXP mrpt::vision::add_3d_deltas_to_points	(	const mrpt::vision::TLandmarkLocationsVec &	landmark_points,
		const mrpt::vector_double &	delta,
		const size_t	delta_first_idx,
		const size_t	delta_num_vals,
		mrpt::vision::TLandmarkLocationsVec &	new_landmark_points,
		const size_t	num_fix_points
	)

For each pose in the vector frame_poses, adds a "delta" increment to the manifold, with the "delta" given in the se(3) Lie algebra:

new_landmark_points[i] = landmark_points[i] + delta[(first_idx+3*i):(first_idx+3*i+2)] , for every pose in landmark_points

Parameters

delta_num_vals

Used just for sanity check, must be equal to "landmark_points.size() * 3"

add_se3_deltas_to_frames()

void VISION_IMPEXP mrpt::vision::add_se3_deltas_to_frames	(	const mrpt::vision::TFramePosesVec &	frame_poses,
		const mrpt::vector_double &	delta,
		const size_t	delta_first_idx,
		const size_t	delta_num_vals,
		mrpt::vision::TFramePosesVec &	new_frame_poses,
		const size_t	num_fix_frames
	)

For each pose in the vector frame_poses, adds a "delta" increment to the manifold, with the "delta" given in the se(3) Lie algebra:

new_frame_poses[i] = frame_poses[i] [+] delta[(first_idx+6*i):(first_idx+6*i+5)] , for every pose in frame_poses

With the left-multiplication convention of the manifold exp(delta) operator, that is:

p <– p [+] delta ==> p <– exp(delta) * p

Parameters

delta_num_vals

Used just for sanity check, must be equal to "frame_poses.size() * 6"

ba_initial_estimate() [1/2]

void VISION_IMPEXP mrpt::vision::ba_initial_estimate	(	const mrpt::vision::TSequenceFeatureObservations &	observations,
		const mrpt::utils::TCamera &	camera_params,
		mrpt::vision::TFramePosesVec &	frame_poses,
		mrpt::vision::TLandmarkLocationsVec &	landmark_points
	)

Fills the frames & landmark points maps with an initial gross estimate from the sequence observations, so they can be fed to bundle adjustment methods.

See also

bundle_adj_full

ba_initial_estimate() [2/2]

void VISION_IMPEXP mrpt::vision::ba_initial_estimate	(	const mrpt::vision::TSequenceFeatureObservations &	observations,
		const mrpt::utils::TCamera &	camera_params,
		mrpt::vision::TFramePosesMap &	frame_poses,
		mrpt::vision::TLandmarkLocationsMap &	landmark_points
	)

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

bundle_adj_full()

double VISION_IMPEXP mrpt::vision::bundle_adj_full	(	const mrpt::vision::TSequenceFeatureObservations &	observations,
		const mrpt::utils::TCamera &	camera_params,
		mrpt::vision::TFramePosesVec &	frame_poses,
		mrpt::vision::TLandmarkLocationsVec &	landmark_points,
		const mrpt::utils::TParametersDouble &	extra_params = mrpt::utils::TParametersDouble(),
		const mrpt::vision::TBundleAdjustmentFeedbackFunctor	user_feedback = NULL
	)

Sparse Levenberg-Marquart solution to bundle adjustment - optimizes all the camera frames & the landmark locations.

At input a gross estimation of the frame poses & the landmark points must be supplied. If you don't have such a starting point, use mrpt::vision::ba_initial_estimate() to compute it.

At output the best found solution will be returned in the variables. Optionally, a functor can be passed for having feedback on the progress at each iteration (you can use it to refresh a GUI, display a progress bar, etc...).

This implementation is almost entirely an adapted version from RobotVision (at OpenSLAM.org) (C) by Hauke Strasdat (Imperial College London), licensed under GNU LGPL. See the related paper: H. Strasdat, J.M.M. Montiel, A.J. Davison: "Scale Drift-Aware Large Scale Monocular SLAM", RSS2010, http://www.roboticsproceedings.org/rss06/p10.html

List of optional parameters in "extra_params":

• "verbose" : Verbose output (default=0)
• "max_iterations": Maximum number of iterations to run (default=50)
• "robust_kernel": If !=0, use a robust kernel against outliers (default=1)
• "kernel_param": The pseudo-huber kernel parameter (default=3)
• "mu": Initial mu for LevMarq (default=-1 -> autoguess)
• "num_fix_frames": Number of first frame poses to don't optimize (keep unmodified as they come in) (default=1: the first pose is the reference and is not modified)
• "num_fix_points": Idem, for the landmarks positions (default=0: optimize all)
• "profiler": If !=0, displays profiling information to the console at return.

Note

In this function, all coordinates are absolute. Camera frames are such that +Z points forward from the focal point (see the figure in mrpt::slam::CObservationImage).

The first frame pose will be not updated since at least one frame must remain fixed.

Parameters

observations	[IN] All the feature observations (WITHOUT distortion), indexed by feature ID as lists of <frame_ID, (x,y)>. See TSequenceFeatureObservations.
camera_params	[IN] The camera parameters, mainly used for the intrinsic 3x3 matrix. Distortion params are ignored since it's assumed that observations are already undistorted pixels.
frame_poses	[IN/OUT] Input: Gross estimation of each frame poses. Output: The found optimal solution.
landmark_points	[IN/OUT] Input: Gross estimation of each landmark point. Output: The found optimal solution.
extra_params	[IN] Optional extra parameters. Read above.
user_feedback	[IN] If provided, this functor will be called at each iteration to provide a feedback to the user.

Returns

The final overall squared error.

reprojectionResiduals() [1/2]

double VISION_IMPEXP mrpt::vision::reprojectionResiduals	(	const mrpt::vision::TSequenceFeatureObservations &	observations,
		const mrpt::utils::TCamera &	camera_params,
		const mrpt::vision::TFramePosesVec &	frame_poses,
		const mrpt::vision::TLandmarkLocationsVec &	landmark_points,
		std::vector< CArray< double, 2 > > &	out_residuals,
		const bool	frame_poses_are_inverse,
		const bool	use_robust_kernel = true,
		const double	kernel_param = 3.0,
		std::vector< double > *	out_kernel_1st_deriv = NULL
	)

Compute reprojection error vector (used from within Bundle Adjustment methods, but can be used in general) See mrpt::vision::bundle_adj_full for a description of most parameters.

Parameters

frame_poses_are_inverse

If set to true, global camera poses are instead of , for each F in frame_poses.

Returns

Overall squared reprojection error.

reprojectionResiduals() [2/2]

double VISION_IMPEXP mrpt::vision::reprojectionResiduals	(	const mrpt::vision::TSequenceFeatureObservations &	observations,
		const mrpt::utils::TCamera &	camera_params,
		const mrpt::vision::TFramePosesMap &	frame_poses,
		const mrpt::vision::TLandmarkLocationsMap &	landmark_points,
		std::vector< CArray< double, 2 > > &	out_residuals,
		const bool	frame_poses_are_inverse,
		const bool	use_robust_kernel = true,
		const double	kernel_param = 3.0,
		std::vector< double > *	out_kernel_1st_deriv = NULL
	)

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.