RGBDRelocalization Class Reference

#include <RGBD/Include/ImFusion/RGBD/RGBDRelocalization.h>

Algorithm for relocalization using RGB-D data. More...

Inheritance diagram for RGBDRelocalization:

Detailed Description

Algorithm for relocalization using RGB-D data.

This class implements a relocalization algorithm based on the paper "Real-Time RGB-D Camera Relocalization", ISMAR 2013. It uses randomized ferns and keyframe matching to estimate camera pose from RGB-D images. The algorithm supports initialization, frame addition, pose database management, and frame localization.

Usage:

• Call init() to configure the relocalization parameters and image sizes.
• Add frames with known poses using addFrame().
• Use localize() to estimate the pose of a new frame by matching it against the database.
• Retrieve all keyframe poses using keyframePoses().
• Use clear() to reset the database.

Important aspects:

• Supports configurable fern count, matching threshold, image sizes, and downsampling.
• Maintains a database of keyframes and their poses for relocalization.
• Returns multiple candidate poses with quality scores for each localization request.
• Not thread-safe.

Example:

RGBDRelocalization relocal;
relocal.init(500, 0.2, 640, 480, 640, 480, 8000, 40000, 8, 2.5);
relocal.addFrame(0, depthImg, colorImg, pose);
std::vector<std::tuple<mat4, double, int>> candidates;
relocal.localize(depthImg, colorImg, candidates, 4);

See also

Relocalization, RGBDReconstructionAlgorithm

Public Member Functions
	RGBDRelocalization ()
	Constructs a new RGBDRelocalization instance.
bool	init (int widthDepth, int heightDepth, int widthColor, int heightColor) override
	Initializes the relocalization algorithm with image sizes.
bool	init (int ferns=500, double threshold=0.2, int widthDepth=640, int heightDepth=480, int widthColor=640, int heightColor=480, float minDepth=8000, float maxDepth=40000, int downsampleFactor=8, double sigmaSmooth=2.5)
	Initializes relocalization parameters.
void	clear () override
	Clears all keyframe data and resets the database.
int	addFrame (int id, TypedImage< float > *imgDepth, TypedImage< unsigned char > *imgColor, const mat4 &T, bool *addedToDatabase=0) override
	Adds a frame to the relocalization database.
int	localize (TypedImage< float > *imgDepth, TypedImage< unsigned char > *imgColor, std::vector< std::tuple< mat4, double, int > > &T, int k=4) override
	Localizes a frame and returns poses for closest matching frames.
void	keyframePoses (std::map< int, mat4 > &T) const
	Returns all keyframe poses.
Public Member Functions inherited from Relocalization
	Relocalization ()
	Constructs the relocalization interface.
virtual	~Relocalization ()
	Destroys the relocalization interface.

Additional Inherited Members
Protected Member Functions inherited from NotCopyable
	NotCopyable (NotCopyable &&) noexcept=default
NotCopyable &	operator= (NotCopyable &&) noexcept=default
	NotCopyable (const NotCopyable &)=delete
NotCopyable &	operator= (const NotCopyable &)=delete

Member Function Documentation

init() [1/2]

bool init ( int widthDepth, int heightDepth, int widthColor, int heightColor )

overridevirtual

Initializes the relocalization algorithm with image sizes.

Parameters

widthDepth	Input depth image width.
heightDepth	Input depth image height.
widthColor	Input color image width.
heightColor	Input color image height.

Returns

True if successful.

Implements Relocalization.

init() [2/2]

bool init	(	int	ferns = 500,
		double	threshold = 0.2,
		int	widthDepth = 640,
		int	heightDepth = 480,
		int	widthColor = 640,
		int	heightColor = 480,
		float	minDepth = 8000,
		float	maxDepth = 40000,
		int	downsampleFactor = 8,
		double	sigmaSmooth = 2.5 )

Initializes relocalization parameters.

Parameters

ferns	Number of ferns.
threshold	Matching threshold for determining whether an image has been seen before. Range [0;1]. Smaller means more keyframes.
widthDepth	Input depth image width.
heightDepth	Input depth image height.
widthColor	Input color image width.
heightColor	Input color image height.
minDepth	Minimum depth value for threshold.
maxDepth	Maximum depth value for threshold.
downsampleFactor	Factor by which input images are downsampled.
sigmaSmooth	Sigma of gaussian kernel with which image is smoothed prior to downsampling.

Returns

True if successful.

clear()

void clear ( )

overridevirtual

Clears all keyframe data and resets the database.

Implements Relocalization.

addFrame()

int addFrame ( int id, TypedImage< float > * imgDepth, TypedImage< unsigned char > * imgColor, const mat4 & T, bool * addedToDatabase = 0 )

overridevirtual

Adds a frame to the relocalization database.

Parameters

	id	Frame id.
	imgDepth	Depth image.
	imgColor	Color image.
	T	Pose for frame.
[out]	addedToDatabase	True if frame was added to pose database, false otherwise.

Returns

Zero if successful.

Implements Relocalization.

localize()

int localize ( TypedImage< float > * imgDepth, TypedImage< unsigned char > * imgColor, std::vector< std::tuple< mat4, double, int > > & T, int k = 4 )

overridevirtual

Localizes a frame and returns poses for closest matching frames.

Parameters

	imgDepth	Depth image.
	imgColor	Color image.
[out]	T	Vector of pose candidates with quality score and frame id (score in [0,1], 1 being better).
	k	Maximum number of poses to return.

Returns

Zero if successful.

Implements Relocalization.

keyframePoses()

void keyframePoses ( std::map< int, mat4 > & T ) const

inline

Returns all keyframe poses.

Parameters

[out]

T

Map of keyframe poses (frame id to pose).

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The documentation for this class was generated from the following file:

• RGBD/Include/ImFusion/RGBD/RGBDRelocalization.h