DcmQuantFloydSteinberg Class Reference

this class implements Floyd-Steinberg error diffusion. More...

List of all members.

Public Member Functions

DcmQuantFloydSteinberg ()

constructor

~DcmQuantFloydSteinberg ()

destructor

OFCondition initialize (unsigned long cols)

initializes the Floyd-Steinberg error vectors for an image with the given number of columns.

void adjust (DcmQuantPixel &px, long col, long maxval)

uses the Floyd-Steinberg error vectors to adjust the color of the current image pixel.

void propagate (const DcmQuantPixel &px, const DcmQuantPixel &mapped, long col)

propagates the Floyd-Steinberg error terms for one pixel.

void startRow (long &col, long &limitcol)

starts error diffusion for a new row.

void finishRow ()

finishes error diffusion for one image row.

void nextCol (long &col) const

increases or decreases the column number depending on the direction flag.

DcmQuantFloydSteinberg ()

constructor

~DcmQuantFloydSteinberg ()

destructor

OFCondition initialize (unsigned long cols)

initializes the Floyd-Steinberg error vectors for an image with the given number of columns.

void adjust (DcmQuantPixel &px, long col, long maxval)

uses the Floyd-Steinberg error vectors to adjust the color of the current image pixel.

void propagate (const DcmQuantPixel &px, const DcmQuantPixel &mapped, long col)

propagates the Floyd-Steinberg error terms for one pixel.

void startRow (long &col, long &limitcol)

starts error diffusion for a new row.

void finishRow ()

finishes error diffusion for one image row.

void nextCol (long &col) const

increases or decreases the column number depending on the direction flag.

Private Member Functions

void cleanup ()

frees all memory allocated by the error vectors

DcmQuantFloydSteinberg (const DcmQuantFloydSteinberg &src)

private undefined copy constructor

DcmQuantFloydSteinberg & operator= (const DcmQuantFloydSteinberg &src)

private undefined copy assignment operator

void cleanup ()

frees all memory allocated by the error vectors

DcmQuantFloydSteinberg (const DcmQuantFloydSteinberg &src)

private undefined copy constructor

DcmQuantFloydSteinberg & operator= (const DcmQuantFloydSteinberg &src)

private undefined copy assignment operator

Private Attributes

long * thisrerr

current red error vector. Points to an array of (columns + 2) entries.

long * nextrerr

red error vector for next row. Points to an array of (columns + 2) entries.

long * thisgerr

current green error vector. Points to an array of (columns + 2) entries.

long * nextgerr

green error vector for next row. Points to an array of (columns + 2) entries.

long * thisberr

current blue error vector. Points to an array of (columns + 2) entries.

long * nextberr

blue error vector for next row. Points to an array of (columns + 2) entries.

long * temperr

temporary pointer used for swapping error vectors

int fs_direction

boolean flag indicating in which direction (left to right/right to left) the FS distribution should be done.

unsigned long columns

number of columns in image

long * thisrerr

current red error vector. Points to an array of (columns + 2) entries.

long * nextrerr

red error vector for next row. Points to an array of (columns + 2) entries.

long * thisgerr

current green error vector. Points to an array of (columns + 2) entries.

long * nextgerr

green error vector for next row. Points to an array of (columns + 2) entries.

long * thisberr

current blue error vector. Points to an array of (columns + 2) entries.

long * nextberr

blue error vector for next row. Points to an array of (columns + 2) entries.

long * temperr

temporary pointer used for swapping error vectors

Detailed Description

this class implements Floyd-Steinberg error diffusion.

It is used during the color quantization of an image.

Definition at line 52 of file diqtfs.h.

Member Function Documentation

void DcmQuantFloydSteinberg::adjust ( DcmQuantPixel & px,

long col,

long maxval

) [inline]

uses the Floyd-Steinberg error vectors to adjust the color of the current image pixel.

Parameters:

px the original image pixel is passed in this parameter. Upon return, the pixel value contains the new value after error diffusion.

col column in which the current pixel is located, must be [0..columns-1]

maxval maximum value for each color component.

Definition at line 75 of file diqtfs.h.
References DcmQuantPixel::assign(), DcmQuantPixel::getBlue(), DcmQuantPixel::getGreen(), and DcmQuantPixel::getRed().

void DcmQuantFloydSteinberg::finishRow ( ) [inline]

finishes error diffusion for one image row.
The direction flag is inverted and the error vectors for the "current" and "next" image row are swapped.
Definition at line 165 of file diqtfs.h.

OFCondition DcmQuantFloydSteinberg::initialize ( unsigned long cols )

initializes the Floyd-Steinberg error vectors for an image with the given number of columns.

Parameters:

cols number of columns in image

Returns:
EC_Normal if successful, an error code otherwise.

void DcmQuantFloydSteinberg::nextCol ( long & col ) const [inline]

increases or decreases the column number depending on the direction flag.

Parameters:

col column number, may become negative

Definition at line 183 of file diqtfs.h.

void DcmQuantFloydSteinberg::propagate ( const DcmQuantPixel & px,

const DcmQuantPixel & mapped,

long col

) [inline]

propagates the Floyd-Steinberg error terms for one pixel.

Parameters:

px color value the current image pixel should have (after adjustment)

mapped color value (selected from the color LUT) the current image pixel really uses

col column in which the current pixel is located, must be [0..columns-1]

Definition at line 94 of file diqtfs.h.
References DcmQuantPixel::getBlue(), DcmQuantPixel::getGreen(), and DcmQuantPixel::getRed().

void DcmQuantFloydSteinberg::startRow ( long & col,

long & limitcol

) [inline]

starts error diffusion for a new row.
The error vectors for the next image row are initialized to zero. The initial and last column of the current row are determined
Parameters:

col initial column for the current row returned in this parameter

limitcol limit column (one past the last valid column) for the current row returned in this parameter. May become negative.

Definition at line 144 of file diqtfs.h.

Member Data Documentation

int DcmQuantFloydSteinberg::fs_direction [private]

boolean flag indicating in which direction (left to right/right to left) the FS distribution should be done.
Flag is inverted after each row.
Definition at line 223 of file diqtfs.h.

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

dcmimage/include/diqtfs.h
debian/libdcmtk0-dev/usr/include/dcmtk/dcmimage/diqtfs.h

Generated on 8 Dec 2004 for OFFIS DCMTK Version 3.5.3 by Doxygen 1.3.9.1


Public Member Functions
	DcmQuantFloydSteinberg ()
	constructor
	~DcmQuantFloydSteinberg ()
	destructor
OFCondition	initialize (unsigned long cols)
	initializes the Floyd-Steinberg error vectors for an image with the given number of columns.
void	adjust (DcmQuantPixel &px, long col, long maxval)
	uses the Floyd-Steinberg error vectors to adjust the color of the current image pixel.
void	propagate (const DcmQuantPixel &px, const DcmQuantPixel &mapped, long col)
	propagates the Floyd-Steinberg error terms for one pixel.
void	startRow (long &col, long &limitcol)
	starts error diffusion for a new row.
void	finishRow ()
	finishes error diffusion for one image row.
void	nextCol (long &col) const
	increases or decreases the column number depending on the direction flag.
	DcmQuantFloydSteinberg ()
	constructor
	~DcmQuantFloydSteinberg ()
	destructor
OFCondition	initialize (unsigned long cols)
	initializes the Floyd-Steinberg error vectors for an image with the given number of columns.
void	adjust (DcmQuantPixel &px, long col, long maxval)
	uses the Floyd-Steinberg error vectors to adjust the color of the current image pixel.
void	propagate (const DcmQuantPixel &px, const DcmQuantPixel &mapped, long col)
	propagates the Floyd-Steinberg error terms for one pixel.
void	startRow (long &col, long &limitcol)
	starts error diffusion for a new row.
void	finishRow ()
	finishes error diffusion for one image row.
void	nextCol (long &col) const
	increases or decreases the column number depending on the direction flag.
Private Member Functions
void	cleanup ()
	frees all memory allocated by the error vectors
	DcmQuantFloydSteinberg (const DcmQuantFloydSteinberg &src)
	private undefined copy constructor
DcmQuantFloydSteinberg &	operator= (const DcmQuantFloydSteinberg &src)
	private undefined copy assignment operator
void	cleanup ()
	frees all memory allocated by the error vectors
	DcmQuantFloydSteinberg (const DcmQuantFloydSteinberg &src)
	private undefined copy constructor
DcmQuantFloydSteinberg &	operator= (const DcmQuantFloydSteinberg &src)
	private undefined copy assignment operator
Private Attributes
long *	thisrerr
	current red error vector. Points to an array of (columns + 2) entries.
long *	nextrerr
	red error vector for next row. Points to an array of (columns + 2) entries.
long *	thisgerr
	current green error vector. Points to an array of (columns + 2) entries.
long *	nextgerr
	green error vector for next row. Points to an array of (columns + 2) entries.
long *	thisberr
	current blue error vector. Points to an array of (columns + 2) entries.
long *	nextberr
	blue error vector for next row. Points to an array of (columns + 2) entries.
long *	temperr
	temporary pointer used for swapping error vectors
int	fs_direction
	boolean flag indicating in which direction (left to right/right to left) the FS distribution should be done.
unsigned long	columns
	number of columns in image
long *	thisrerr
	current red error vector. Points to an array of (columns + 2) entries.
long *	nextrerr
	red error vector for next row. Points to an array of (columns + 2) entries.
long *	thisgerr
	current green error vector. Points to an array of (columns + 2) entries.
long *	nextgerr
	green error vector for next row. Points to an array of (columns + 2) entries.
long *	thisberr
	current blue error vector. Points to an array of (columns + 2) entries.
long *	nextberr
	blue error vector for next row. Points to an array of (columns + 2) entries.
long *	temperr
	temporary pointer used for swapping error vectors