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The motion history image class. More...

#include <ncvMotionHistoryImage.h>

Collaboration diagram for CMotionHistoryImage:

Collaboration graph

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List of all members.


Public Member Functions
virtual IMPORT_C	~CMotionHistoryImage ()
	Destructor.
IMPORT_C void	AddImage (CNokiaCVImage &aImage)
	Add an image to the motion history.
IMPORT_C void	GetImage (CNokiaCVImage &aImage)
	Get a CNokiaCVImage containing the motion history image.
Static Public Member Functions
static IMPORT_C CMotionHistoryImage *	NewL (CNokiaCVImage &aImage, const TInt aHistorySize)
	Construct CMotionHistoryImage from the first image of motion history.
Protected Member Functions
	CMotionHistoryImage (const TSize &iImageSize, const TInt aHistorySize)
	Constructor.
void	ConstructL (CNokiaCVImage &aImage)
	Second-phase constructor.

Detailed Description

The motion history image class.

This class computes a motion history image (MHI) for a series of input frames. The MHI is a grayscale bitmap in which recently moved pixels are represent with bright values and "older" with darker values. Frame-by-frame the values from previous frames are decayed linearly.

The decay and the length of the history is controlled with a single parameter aHistorySize that is equal to the number of the frames that are included in the MHI computation.

See http://www.cse.ohio-state.edu/~jwdavis/CVL/Publications/TR-402.pdf and http://www.cse.ohio-state.edu/~jwdavis/CVL/Research/MHI/mhi.html for more information.

Definition at line 30 of file ncvMotionHistoryImage.h.

Constructor & Destructor Documentation

CMotionHistoryImage::CMotionHistoryImage	(	const TSize &	iImageSize,
		const TInt	aHistorySize
	)			`[protected]`

Constructor.

Parameters:

	aImageSize	Size of the images.
	aHistorySize	Maximum number of images in the history.

Member Function Documentation

static IMPORT_C CMotionHistoryImage* CMotionHistoryImage::NewL	(	CNokiaCVImage &	aImage,
		const TInt	aHistorySize
	)			`[static]`

Construct CMotionHistoryImage from the first image of motion history.

Parameters:

	aImage	First image of motion history.
	aHistorySize	duration of the motion history (tau), the number of frames that are used to compute MHI. (inverse of decay)

Note:

All images must be black and white images with display type of EGray2.

All images used with an instance must be of the same, nonzero size as the initialization image.

aHistorySize must be an integer larger than 1.

the function can leave

Returns:: CMotionHistoryImage*

IMPORT_C void CMotionHistoryImage::AddImage ( CNokiaCVImage & aImage )

Add an image to the motion history.

Parameters:

aImage

CNokiaCVImage containing the next image of motion history.

Note:: All images must be black and white images with display type of EGray2.

IMPORT_C void CMotionHistoryImage::GetImage ( CNokiaCVImage & aImage )

Get a CNokiaCVImage containing the motion history image.

Parameters:

aImage

CNokiaCVImage into which insert the motion history image.

Note:: aImage must be of display type EGray256 and of the same size as the images used with AddImage(CNokiaCVImage& aImage).

Returns:: CNokiaCVImage*

void CMotionHistoryImage::ConstructL ( CNokiaCVImage & aImage ) [protected]

Second-phase constructor.

Parameters:

aImage

First image.

See also:: NewL(CNokiaCVImage& aImage, const TInt aHistorySize) for params.

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

ncvMotionHistoryImage.h

Generated on Tue Jul 10 22:58:42 2007 for NokiaComputerVisionLibrary by

1.5.2

Public Member Functions

Static Public Member Functions

Protected Member Functions

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation