Calibrates one or more cameras from homographies and 2D/3D correspondances. More...

#include <CamCalibration.h>

Classes
struct	s_struct_camera
	Structure specifying a single camera.
struct	s_struct_homography
	Structure specifying one homography of a single camera.
struct	s_struct_intrinsic
	Structure specifying a camera's intrinsic parameters.
struct	s_struct_optimal
	The optimal structure.
struct	s_struct_plane
	Structure specifying 2D-to-2D correspondances.
struct	s_struct_points
	Transfer structure for AddHomography(). More...
struct	s_struct_solution
	A candidate solution created by the probabilistic filter.

Public Member Functions
	CamCalibration ()
	Constructor of the CamCalibration class.
	~CamCalibration ()
	Deconstructor of the CamCalibration class.
void	AddCamera (int width, int height)
	Add a camera.
bool	AddHomography (int c)
	Add an empty homography (without data) to camera c.
bool	AddHomography (int c, std::vector< CamCalibration::s_struct_points > p, CvMat *ready)
	Add a homography with data to camera c.
bool	StoreHomographiesToFile (char *file_name)
	Stores initial homography structure to file.
bool	LoadHomographiesFromFile (char *file_name)
	Loads initial homography structure from file.
bool	Calibrate (int p_HomographyNum, int p_PreFilter, int p_Solutions, double p_PreFilter_a, double p_PreFilter_b, double p_PreFilter_c, double p_InitialGuess_a, double p_InitialGuess_b, double p_InitialGuess_c, int p_Iterations, double p_Epsilon, double p_PostFilter)
	Starts the camera calibration process.
void	PrintOptimizedResultsToFile1 ()
	Prints resulting matrices seperated to 3 files.
void	PrintOptimizedResultsToFile2 (char file_descriptor, bool create_png=false, char sequence_descriptor="", char *png_descriptor="", int c_start=0, int h_start=0)
	Prints resulting projection matrices to many separated files.
void	PlotPointsToImagesAfterOptimization ()
void	ClearAll ()

Static Public Member Functions
static void	ExtractRotationTranslationFrom3x4Matrix (CvMat RotTrans, CvMat Rot, CvMat *Trans)
	Decomposes RotTrans into Rot and Trans.
static void	ComposeRotationTranslationTo3x4Matrix (CvMat RotTrans, CvMat Rot, CvMat *Trans)
	Composes Rot and Trans to RotTrans.
static void	Mat3x4Mul (CvMat m_A, CvMat m_B, CvMat *m_C)
	Multiplies 3x4 matrices m_A and m_B to m_C.
static void	Mat3x4Inverse (CvMat m_A, CvMat m_B)
	Inverts 3x4 matrix m_A and stores result to m_B.
static void	HomogenousNormalizeVector (CvMat *mat)
	Divides mat by its last element.

Friends
struct	ProjObs

Detailed Description

Calibrates one or more cameras from homographies and 2D/3D correspondances.

Implements functions to calibrate a set of cameras at one time using planar 2D-2D correspondances. Provides functions to output the resulting matrices including intrinsic and extrinsic camera parameters as well as statistical functions.

See singlecalib.cpp for a single camera simple example, or multicam.cpp for a complete example.

Author: Andreas Geiger; Computer Vision Laboratory, http://cvlab.epfl.ch/; Swiss Federal Institute of Technology, Lausanne

Date: 20.02.2006

Examples:: fullcalib.cpp, multicam.cpp, multigl.cpp, and singlecalib.cpp.

Definition at line 37 of file CamCalibration.h.

Constructor & Destructor Documentation

CamCalibration::CamCalibration ( )

Constructor of the CamCalibration class.

Definition at line 84 of file CamCalibration.cpp.

CamCalibration::~CamCalibration ( )

Deconstructor of the CamCalibration class.

The class should be destroyed with the deconstructor after having done its job.

Definition at line 91 of file CamCalibration.cpp.

References ClearAll().

Member Function Documentation

void CamCalibration::AddCamera	(	int	width,
		int	height
	)

Add a camera.

This function adds a camera with the specified width and height to the CamCalibration class. Before adding a homography you should create the camera. The first added camera is numbered 0, the following with increasing numbers.

Examples:: fullcalib.cpp, multicam.cpp, multigl.cpp, and singlecalib.cpp.

Definition at line 105 of file CamCalibration.cpp.

Referenced by geom_calib_start(), geometric_calibration(), LoadHomographiesFromFile(), and main().

bool CamCalibration::AddHomography ( int c )

Add an empty homography (without data) to camera c.

This adds an empty homography to the camera specified by c. If the camera does not exist this function returns false, otherwise true. This function should be used if the homographie is not available (i.e. due to too much noise in the picture).

Examples:: fullcalib.cpp, multicam.cpp, multigl.cpp, and singlecalib.cpp.

Definition at line 109 of file CamCalibration.cpp.

Referenced by add_detected_homography(), geom_calib_idle(), geometric_calibration(), and LoadHomographiesFromFile().

bool CamCalibration::AddHomography	(	int	c,
		std::vector< CamCalibration::s_struct_points >	p,
		CvMat *	ready
	)

Add a homography with data to camera c.

This adds a homography to the camera specified by c. If the camera does not exist this function returns false, otherwise true. The parameter p specifies the array of correspondances described above, n is the corresponcance number and ready specifies a matrix with the homography in OpenCV format. If ready equals NULL the homography is calculated internally by the class. Nevertheless it is recommanded to provide the homography here!

Definition at line 125 of file CamCalibration.cpp.

References cvmSet().

bool CamCalibration::Calibrate	(	int	p_HomographyNum,
		int	p_PreFilter,
		int	p_Solutions,
		double	p_PreFilter_a,
		double	p_PreFilter_b,
		double	p_PreFilter_c,
		double	p_InitialGuess_a,
		double	p_InitialGuess_b,
		double	p_InitialGuess_c,
		int	p_Iterations,
		double	p_Epsilon,
		double	p_PostFilter
	)

Starts the camera calibration process.

After adding all cameras and homographies this function will estimate the intrinsic and extrinsic parameters of the cameras as well as the rotation and translation of the image pattern at every time step. You have to specify a number of parameters here:

p_HomographyNum : Maximal number of homographies to use for optimization.
p_PreFilter: Filtering method to use: 0=Greedy, 1=Padding, 2=Probabilistic
p_PreFilter_a: For Padding filter: Specifies ratio, for Probabilistic filter: specifies weight 1
p_PreFilter_b: For Probabilistic filter: specifies weight 2
p_PreFilter_c: For Probabilistic filter: specifies weight 3
p_InitialGuess_a: Specifies alpha
p_InitialGuess_b: Specifies beta
p_InitialGuess_c: Specifies gamma
p_Iterations: Specifies maximal number of Levenberg-Marquardt iterations
p_Epsilon: Specifies maximal accuracy of Levenberg-Marquardt optimization
p_PostFilter: Specifies post filter threshold tau

Note: For a more detailed parameter description have a look at the report attached to this project!

Examples:: fullcalib.cpp, multicam.cpp, multigl.cpp, and singlecalib.cpp.

Definition at line 579 of file CamCalibration.cpp.

Referenced by geom_calib_idle(), geometric_calibration(), and main().

void CamCalibration::ClearAll ( )

Definition at line 95 of file CamCalibration.cpp.

Referenced by ~CamCalibration().

void CamCalibration::ComposeRotationTranslationTo3x4Matrix	(	CvMat *	RotTrans,
		CvMat *	Rot,
		CvMat *	Trans
	)

static

Composes Rot and Trans to RotTrans.

Note: By definition, the translation vector is inversed.

Definition at line 780 of file CamCalibration.cpp.

References cvmGet(), and cvmSet().

Referenced by Mat3x4Inverse().

void CamCalibration::ExtractRotationTranslationFrom3x4Matrix	(	CvMat *	RotTrans,
		CvMat *	Rot,
		CvMat *	Trans
	)

static

Decomposes RotTrans into Rot and Trans.

Note: By definition, the translation vector is inversed.

Definition at line 761 of file CamCalibration.cpp.

References cvmGet(), and cvmSet().

Referenced by PoseObs::eval_func(), ProjObs::eval_func(), CamAugmentation::LoadOptimalStructureFromFile(), and Mat3x4Inverse().

void CamCalibration::HomogenousNormalizeVector ( CvMat * mat )

static

Divides mat by its last element.

Definition at line 662 of file CamCalibration.cpp.

References cvmGet(), and cvmSet().

Referenced by PoseObs::eval_func(), ProjObs::eval_func(), and PlotPointsToImagesAfterOptimization().

bool CamCalibration::LoadHomographiesFromFile ( char * file_name )

Loads initial homography structure from file.

Loads the whole homography structure from a file specified by file_name. Recovers the homographies you saved with StoreHomographiesToFile().

Definition at line 209 of file CamCalibration.cpp.

References AddCamera(), AddHomography(), and homography::cvmSet().

void CamCalibration::Mat3x4Inverse	(	CvMat *	m_A,
		CvMat *	m_B
	)

static

Inverts 3x4 matrix m_A and stores result to m_B.

Definition at line 821 of file CamCalibration.cpp.

References ComposeRotationTranslationTo3x4Matrix(), and ExtractRotationTranslationFrom3x4Matrix().

void CamCalibration::Mat3x4Mul	(	CvMat *	m_A,
		CvMat *	m_B,
		CvMat *	m_C
	)

static

Multiplies 3x4 matrices m_A and m_B to m_C.

Examples:: multigl.cpp.

Definition at line 811 of file CamCalibration.cpp.

Referenced by PoseObs::eval_func(), ProjObs::eval_func(), CamAugmentation::GetProjectionMatrix(), photo_draw(), PlotPointsToImagesAfterOptimization(), and PrintOptimizedResultsToFile2().

void CamCalibration::PlotPointsToImagesAfterOptimization ( )

!!!!!!!!!!!!!!

Definition at line 1859 of file CamCalibration.cpp.

References cvmGet(), cvPoint(), HomogenousNormalizeVector(), and Mat3x4Mul().

void CamCalibration::PrintOptimizedResultsToFile1 ( )

Prints resulting matrices seperated to 3 files.

The output files are:

"camera_c" : Contains the resulting camera calibration matrices (intrinsic parameters)
"camera_r_t" : Contains the resulting camera rotation/translation matrices. These matrices transform a point from the reference system to the specified camera coordinate system.
"view_r_t" : Contains the resulting view rotation/translation matrices. These matrices transform a point from the specified view coordinate system to the reference system.

Note: A projection matrix can be built by applying the following matrix multiplication: camera_c*camera_r_t*view_r_t

Examples:: fullcalib.cpp, multicam.cpp, multigl.cpp, and singlecalib.cpp.

Definition at line 2357 of file CamCalibration.cpp.

References showmatrix_file().

Referenced by geom_calib_idle(), geometric_calibration(), and main().

void CamCalibration::PrintOptimizedResultsToFile2	(	char *	file_descriptor,
		bool	create_png = `false`,
		char *	sequence_descriptor = `""`,
		char *	png_descriptor = `""`,
		int	c_start = `0`,
		int	h_start = `0`
	)

Prints resulting projection matrices to many separated files.

This function calculates a projection matrix for each view-to-camera combination available and stores the result to separated files (1 file per matrix). You have to specify a file_descripter, which contains 2x "%04d" or similar. The first indicates the camera number, the second stands for the view number. A possible example is given by: "cam%04d\\img%04d.tdir".
Please note that if you use directories (like this example demonstrates), they are NOT created, but have to exist before. Otherwise the results will not be saved.
If you want to create png files into a new directory, simply enable the create_png flag and set the corresponding parameters. The directories have to exist before, for image creation, too.

Definition at line 2395 of file CamCalibration.cpp.

References cvmGet(), Mat3x4Mul(), and showmatrix_file().

bool CamCalibration::StoreHomographiesToFile ( char * file_name )

Stores initial homography structure to file.

Stores the whole homography structure to a file specified by file_name. This function is useful, if the aquiring system you use takes time and you want to tune parameters without waiting each time you run the optimization.

Definition at line 162 of file CamCalibration.cpp.

References cvmGet(), and homography::cvmGet().

Friends And Related Function Documentation

friend struct ProjObs

friend

Definition at line 840 of file CamCalibration.h.

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

/home/adrien/Téléchargements/bazar/bazar-1.3.1/garfeild/calib/CamCalibration.h
/home/adrien/Téléchargements/bazar/bazar-1.3.1/garfeild/calib/CamCalibration.cpp

Classes

Public Member Functions

Static Public Member Functions

Friends

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Friends And Related Function Documentation