KudanArbiTracker Class Reference

The Kudan markerless tracker, which tracks the content of an image stream and gives a 3D pose for each frame. More...

#include <KudanCV.h>

Classes
class	Private

Public Member Functions
	KudanArbiTracker ()
	~KudanArbiTracker ()
void	start (KudanVector3 startPosition, KudanQuaternion startOrientation)
void	start (KudanMatrix4 startTransform)
void	stop ()
bool	processFrame (const unsigned char *image, int width, int height, int channels, int padding, bool requireFlip)
KudanVector3	getPosition ()
KudanQuaternion	getOrientation ()
void	setSensedOrientation (KudanQuaternion sensedOrientation)
bool	isTracking ()
bool	hasCameraCalibration ()
void	setCameraParameters (KudanCameraParameters &cameraParameters)
KudanCameraParameters &	getCameraParameters ()
KudanMatrix3	getCameraMatrix ()
KudanMatrix4	getProjectionMatrix (float nearPlane, float farPlane)
void	setApiKey (std::string apiKey)

Detailed Description

The Kudan markerless tracker, which tracks the content of an image stream and gives a 3D pose for each frame.

Constructor & Destructor Documentation

KudanArbiTracker()

KudanArbiTracker::KudanArbiTracker

(

)

Default constructor that calls initialise()

~KudanArbiTracker()

KudanArbiTracker::~KudanArbiTracker

(

)

Destructor which de-initialises the tracker

Member Function Documentation

getCameraMatrix()

KudanMatrix3 KudanArbiTracker::getCameraMatrix

(

)

Get the calibration matrix for this camera, derived from the intrinsic parameters. This is a 3x3 matrix represented as the float array within a KudanMatrix3

Returns

A KudanMatrix3 representing the intrinsic parameters

Exceptions

KudanException

is thrown if the parameters have not been set

getCameraParameters()

KudanCameraParameters & KudanArbiTracker::getCameraParameters

(

)

Get a (reference to) the camera parameters set on the tracker.

Returns

A reference to a KudanCameraParameters object. Altering this will change the one stored in the tracker

getOrientation()

KudanQuaternion KudanArbiTracker::getOrientation

(

)

Get the pose of the tracked coordinate frame. This is the orientation of the tracked frame, about its centre

Returns

a KudanQuaternion which represents a 4D quaternion (x, y, z, w)

getPosition()

KudanVector3 KudanArbiTracker::getPosition

(

)

Get the pose of the tracked coordinate frame. This is the position of the centre of the tracked frame with respect to the camera centre

Returns

A KudanVector3 which represents a 3D point (x, y, z)

getProjectionMatrix()

KudanMatrix4 KudanArbiTracker::getProjectionMatrix	(	float	nearPlane,
		float	farPlane
	)

Get the projection matrix for this camera. This is derived from the intrinsic parameters and the given clipping planes. This is a 4x4 matrix represented as the float array within a KudanMatrix.

Parameters

nearPlane,farPlane

The clipping planes to be used for rendering (not part of the camera parameters).

Returns

A KudanMatrix representing the intrinsic parameters plus clipping planes.

Exceptions

KudanException

is thrown if the parameters have not been set

hasCameraCalibration()

bool KudanArbiTracker::hasCameraCalibration

(

)

Queries if a calibration has been set

Returns

A boolean indicating if calibration data are available.

isTracking()

bool KudanArbiTracker::isTracking

(

)

Indicates whether tracking is currently happening

Returns

A boolean, true iff tracking is running

processFrame()

bool KudanArbiTracker::processFrame	(	const unsigned char *	image,
		int	width,
		int	height,
		int	channels,
		int	padding,
		bool	requireFlip
	)

Process a new frame. If tracking is successful, the position and orientation are updated to the new pose for this frame. This will fail (return false) if a valid license is not set, or if ArbiTrack is not available for the current platform.

Parameters

image	8bpp greyscale image data.
width,height	size of the image data matrix
channels	number of channels in the image (mono, colour, colour+alpha)
padding	the number of bytes to ignore at the end of each line
requireFlip	some devices provide the image upside down (rotation of 180 degrees). This flips the image (in both axes) before processing

Returns

A boolean indicating whether tracking happened (true) or not (false)

Exceptions

KudanException

is thrown if there is no calibration data or an empty image.

setApiKey()

void KudanArbiTracker::setApiKey

(

std::string

apiKey

)

A valid API key needs to be set before calling processFrame.

Parameters

apiKey

a valid key can only be acquired from Kudan.

setCameraParameters()

void KudanArbiTracker::setCameraParameters

(

KudanCameraParameters &

cameraParameters

)

Sets the camera parameters using given camera parameters

Parameters

cameraParameters

Object of KudanCameraParameters which defines the camera intrinsics and image size

Exceptions

KudanException

is thrown if the parameters are invalid

setSensedOrientation()

void KudanArbiTracker::setSensedOrientation

(

KudanQuaternion

sensedOrientation

)

Arbitrack requires that an orientation estimate be provided from some external sensor (e.g. gyroscope, IMU). Without this, Arbitrack will always return the identity rotation. This must be called BEFORE calling processFrame for a given frame Use this function to set the orientation value which will be fused with the image based tracking

Parameters

sensedOrientation

An orientation represented by a quaternion

start() [1/2]

void KudanArbiTracker::start

(

KudanMatrix4

startTransform

)

Start the tracker. The tracker is started at the given pose (specified as a 4x4 transformation matrix).

Parameters

startTransform

A 4x4 matrix representing the initial pose of the tracker coordinate frame with repsect to the camera

start() [2/2]

void KudanArbiTracker::start	(	KudanVector3	startPosition,
		KudanQuaternion	startOrientation
	)

Start the tracker. The tracker is started at the given pose (specified as position and orientation).

Parameters

startPosition	Starting position in 3D of the tracker coordinate frame with respect to the camera origin
startOrientation	Starting otientation (about its own centre) of the tracker coordinate frame

stop()

void KudanArbiTracker::stop

(

)

Stop tracking

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

• KudanCV.h
• KudanCV.cpp