lti::camshiftTracker Class Reference

This is the implementation of the CAMSHIFT (Continuously Adaptive Mean Shift) Tracking algorithm as described in: G.Bradski, "Computer Vision Face Tracking For Use in a Perceptual User Interface", IEEE Workshop on Applic.Comp.Vis.,1998. More...

#include <ltiCamshiftTracker.h>

Inheritance diagram for lti::camshiftTracker:

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Collaboration diagram for lti::camshiftTracker:

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List of all members.

Classes
class	parameters
	the parameters for the class camshiftTracker More...
Public Member Functions
	camshiftTracker ()
	camshiftTracker (const camshiftTracker &other)
virtual	~camshiftTracker ()
virtual const char *	getTypeName () const
bool	apply (const channel &src, rectangle &window)
bool	apply (const channel8 &src, rectangle &window)
bool	reset ()
bool	isInitialized ()
bool	isValid ()
double	getOrientation ()
double	getLength ()
double	getWidth ()
tpoint< float >	getCenter ()
camshiftTracker &	copy (const camshiftTracker &other)
virtual functor *	clone () const
const parameters &	getParameters () const

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Detailed Description

This is the implementation of the CAMSHIFT (Continuously Adaptive Mean Shift) Tracking algorithm as described in: G.Bradski, "Computer Vision Face Tracking For Use in a Perceptual User Interface", IEEE Workshop on Applic.Comp.Vis.,1998.

It tracks a rectangular search window in a channel/channel8, which must contain probability information of relevant image content (e.g. a skinProbabilityMap). It uses an iterative gradient ascent algorithm, that finds the peak, which is the closest to the specified window.

Use this by calling an apply on subsequent images and thereby passing the last result. Nevertheless, it is possible to control rectangle size and position manually.

After an apply you can get Information about the distribution inside the search window (e.g. orientation). Use the getXXX() methods to do so.

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Constructor & Destructor Documentation

lti::camshiftTracker::camshiftTracker

(

)

default constructor

lti::camshiftTracker::camshiftTracker

(

const camshiftTracker &

other

)

copy constructor

Parameters:

other

the object to be copied

virtual lti::camshiftTracker::~camshiftTracker

(

)

[virtual]

destructor

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Member Function Documentation

bool lti::camshiftTracker::apply	(	const channel8 &	src,
		rectangle &	window
	)

Centers the given search window on the nearest probability peak.

Tracking is realised by using this rectangle in the next call of this function. Information about the distribution inside the search window is stored and can be retrieved by using the getXXXX() methods of this functor.

Parameters:

	src	channel8 with the source data. Should represent a probability map (prob(0)=0.0 and prob(255)=1.0)
	window	the tracking window. Result will be left here.

Returns:

true if apply successful or false otherwise.

bool lti::camshiftTracker::apply	(	const channel &	src,
		rectangle &	window
	)

Centers the given search window on the nearest probability peak.

Tracking is realised by using this rectangle in the next call of this function. Information about the distribution inside the search window is stored and can be retrieved by using the getXXXX() methods of this functor.

Parameters:

	src	channel with the source data. Should represent a probability map with values between 0.0 and 1.0
	window	the tracking window. Result will be left here.

Returns:

true if apply successful or false otherwise.

virtual functor* lti::camshiftTracker::clone

(

)

const [virtual]

returns a pointer to a clone of this functor.

Implements lti::functor.

camshiftTracker& lti::camshiftTracker::copy

(

const camshiftTracker &

other

)

copy data of "other" functor.

Parameters:

other

the functor to be copied

Returns:

a reference to this functor object

Reimplemented from lti::functor.

tpoint<float> lti::camshiftTracker::getCenter

(

)

Returns center of current internal distribution state.

double lti::camshiftTracker::getLength

(

)

Returns length of current internal distribution state.

double lti::camshiftTracker::getOrientation

(

)

Returns Main orientation (-Pi/2 to +Pi/2) of current internal distribution state.

const parameters& lti::camshiftTracker::getParameters

(

)

const

returns used parameters

Reimplemented from lti::modifier.

virtual const char* lti::camshiftTracker::getTypeName

(

)

const [virtual]

returns the name of this type ("camshiftTracker")

Reimplemented from lti::modifier.

double lti::camshiftTracker::getWidth

(

)

Returns width of current internal distribution state.

bool lti::camshiftTracker::isInitialized

(

)

Tells, if tracker is initialized.

bool lti::camshiftTracker::isValid

(

)

Tells, if last tracking attempt delivered valid data.

bool lti::camshiftTracker::reset

(

)

Resets the internal state but not the parameters.

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

• ltiCamshiftTracker.h