DSP

Enumerations
enum	CxImage::ImageOpType {   CxImage::OpAdd, CxImage::OpAnd, CxImage::OpXor, CxImage::OpOr,   CxImage::OpMask, CxImage::OpSrcCopy, CxImage::OpDstCopy, CxImage::OpSub,   CxImage::OpSrcBlend, CxImage::OpScreen, CxImage::OpAvg }
Functions
bool	CxImage::Contour ()
bool	CxImage::HistogramStretch (long method=0, double threshold=0)
bool	CxImage::HistogramEqualize ()
bool	CxImage::HistogramNormalize ()
bool	CxImage::HistogramRoot ()
bool	CxImage::HistogramLog ()
long	CxImage::Histogram (long *red, long *green=0, long *blue=0, long *gray=0, long colorspace=0)
bool	CxImage::Jitter (long radius=2)
bool	CxImage::Repair (float radius=0.25f, long niterations=1, long colorspace=0)
bool	CxImage::Combine (CxImage *r, CxImage *g, CxImage *b, CxImage *a, long colorspace=0)
bool	CxImage::FFT2 (CxImage *srcReal, CxImage *srcImag, CxImage *dstReal, CxImage *dstImag, long direction=1, bool bForceFFT=true, bool bMagnitude=true)
bool	CxImage::Noise (long level)
bool	CxImage::Median (long Ksize=3)
bool	CxImage::Gamma (float gamma)
bool	CxImage::GammaRGB (float gammaR, float gammaG, float gammaB)
bool	CxImage::ShiftRGB (long r, long g, long b)
bool	CxImage::Threshold (BYTE level)
bool	CxImage::Threshold (CxImage *pThresholdMask)
bool	CxImage::Threshold2 (BYTE level, bool bDirection, RGBQUAD nBkgndColor, bool bSetAlpha=false)
bool	CxImage::Colorize (BYTE hue, BYTE sat, float blend=1.0f)
bool	CxImage::Light (long brightness, long contrast=0)
float	CxImage::Mean ()
bool	CxImage::Filter (long *kernel, long Ksize, long Kfactor, long Koffset)
bool	CxImage::Erode (long Ksize=2)
bool	CxImage::Dilate (long Ksize=2)
bool	CxImage::Edge (long Ksize=2)
void	CxImage::HuePalette (float correction=1)
void	CxImage::Mix (CxImage &imgsrc2, ImageOpType op, long lXOffset=0, long lYOffset=0, bool bMixAlpha=false)
void	CxImage::MixFrom (CxImage &imagesrc2, long lXOffset, long lYOffset)
bool	CxImage::UnsharpMask (float radius=5.0f, float amount=0.5f, int threshold=0)
bool	CxImage::Lut (BYTE *pLut)
bool	CxImage::Lut (BYTE *pLutR, BYTE *pLutG, BYTE *pLutB, BYTE *pLutA=0)
bool	CxImage::GaussianBlur (float radius=1.0f, CxImage *iDst=0)
bool	CxImage::TextBlur (BYTE threshold=100, BYTE decay=2, BYTE max_depth=5, bool bBlurHorizontal=true, bool bBlurVertical=true, CxImage *iDst=0)
bool	CxImage::SelectiveBlur (float radius=1.0f, BYTE threshold=25, CxImage *iDst=0)
bool	CxImage::Solarize (BYTE level=128, bool bLinkedChannels=true)
bool	CxImage::FloodFill (const long xStart, const long yStart, const RGBQUAD cFillColor, const BYTE tolerance=0, BYTE nOpacity=255, const bool bSelectFilledArea=false, const BYTE nSelectionLevel=255)
bool	CxImage::Saturate (const long saturation, const long colorspace=1)
bool	CxImage::ConvertColorSpace (const long dstColorSpace, const long srcColorSpace)
int	CxImage::OptimalThreshold (long method=0, RECT *pBox=0, CxImage *pContrastMask=0)
bool	CxImage::AdaptiveThreshold (long method=0, long nBoxSize=64, CxImage *pContrastMask=0, long nBias=0, float fGlobalLocalBalance=0.5f)

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Detailed Description

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Enumeration Type Documentation

enum CxImage::ImageOpType [inherited]

Enumerator:

OpAdd
OpAnd
OpXor
OpOr
OpMask
OpSrcCopy
OpDstCopy
OpSub
OpSrcBlend
OpScreen
OpAvg

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Function Documentation

bool CxImage::AdaptiveThreshold	(	long	method = 0,
		long	nBoxSize = 64,
		CxImage *	pContrastMask = 0,
		long	nBias = 0,
		float	fGlobalLocalBalance = 0.5f
	)			[inherited]

Converts the image to B&W, using an optimal threshold mask

Parameters:

	method,:	0 = average all methods (default); 1 = Otsu; 2 = Kittler & Illingworth; 3 = max entropy; 4 = potential difference;
	nBoxSize,:	the image is divided into "nBoxSize x nBoxSize" blocks, from where the threshold is computed; min = 8; default = 64.
	pContrastMask,:	limit the computation only in regions with contrasted (!=0) pixels; default = 0.
	nBias,:	global offset added to the threshold mask; default = 0.
	fGlobalLocalBalance,:	balance between local and global threshold. default = 0.5 fGlobalLocalBalance can be from 0.0 (use only local threshold) to 1.0 (use only global threshold) the pContrastMask image must be grayscale with same with and height of the current image,

Returns:

true if everything is ok.

See also:

OptimalThreshold

bool CxImage::Colorize	(	BYTE	hue,
		BYTE	sat,
		float	blend = 1.0f
	)			[inherited]

Replaces the original hue and saturation values.

Parameters:

	hue,:	hue
	sat,:	saturation
	blend,:	can be from 0 (no effect) to 1 (full effect)

Returns:

true if everything is ok

bool CxImage::Combine	(	CxImage *	r,
		CxImage *	g,
		CxImage *	b,
		CxImage *	a,
		long	colorspace = 0
	)			[inherited]

Combines different color components into a single image

Parameters:

	r,g,b,:	color channels
	a,:	alpha layer, can be NULL
	colorspace,:	0 = RGB, 1 = HSL, 2 = YUV, 3 = YIQ, 4 = XYZ

Returns:

true if everything is ok

bool CxImage::Contour

(

)

[inherited]

Enhance the variations between adjacent pixels. Similar results can be achieved using Filter(), but the algorithms are different both in Edge() and in Contour().

Returns:

true if everything is ok

bool CxImage::ConvertColorSpace	(	const long	dstColorSpace,
		const long	srcColorSpace
	)			[inherited]

Converts the RGB triplets to and from different colorspace

Parameters:

	dstColorSpace,:	destination colorspace; 0 = RGB, 1 = HSL, 2 = YUV, 3 = YIQ, 4 = XYZ
	srcColorSpace,:	source colorspace; 0 = RGB, 1 = HSL, 2 = YUV, 3 = YIQ, 4 = XYZ

Returns:

true if everything is ok

bool CxImage::Dilate

(

long

Ksize = 2

)

[inherited]

Enhance the light areas of the image

Parameters:

Ksize,:

size of the kernel.

Returns:

true if everything is ok

bool CxImage::Edge

(

long

Ksize = 2

)

[inherited]

Enhance the variations between adjacent pixels. Similar results can be achieved using Filter(), but the algorithms are different both in Edge() and in Contour().

Parameters:

Ksize,:

size of the kernel.

Returns:

true if everything is ok

bool CxImage::Erode

(

long

Ksize = 2

)

[inherited]

Enhance the dark areas of the image

Parameters:

Ksize,:

size of the kernel.

Returns:

true if everything is ok

bool CxImage::FFT2	(	CxImage *	srcReal,
		CxImage *	srcImag,
		CxImage *	dstReal,
		CxImage *	dstImag,
		long	direction = 1,
		bool	bForceFFT = true,
		bool	bMagnitude = true
	)			[inherited]

Computes the bidimensional FFT or DFT of the image.

• The images are processed as grayscale
• If the dimensions of the image are a power of, 2 the FFT is performed automatically.
• If dstReal and/or dstImag are NULL, the resulting images replaces the original(s).
• Note: with 8 bits there is a HUGE loss in the dynamics. The function tries to keep an acceptable SNR, but 8bit = 48dB...

Parameters:

	srcReal,srcImag,:	source images: One can be NULL, but not both
	dstReal,dstImag,:	destination images. Can be NULL.
	direction,:	1 = forward, -1 = inverse.
	bForceFFT,:	if true, the images are resampled to make the dimensions a power of 2.
	bMagnitude,:	if true, the real part returns the magnitude, the imaginary part returns the phase

Returns:

true if everything is ok

bool CxImage::Filter	(	long *	kernel,
		long	Ksize,
		long	Kfactor,
		long	Koffset
	)			[inherited]

2D linear filter

Parameters:

	kernel,:	convolving matrix, in row format.
	Ksize,:	size of the kernel.
	Kfactor,:	normalization constant.
	Koffset,:	bias. Example: the "soften" filter uses this kernel: 1 1 1 1 8 1 1 1 1 the function needs: kernel={1,1,1,1,8,1,1,1,1}; Ksize=3; Kfactor=16; Koffset=0;

Returns:

true if everything is ok

bool CxImage::FloodFill	(	const long	xStart,
		const long	yStart,
		const RGBQUAD	cFillColor,
		const BYTE	nTolerance = 0,
		BYTE	nOpacity = 255,
		const bool	bSelectFilledArea = false,
		const BYTE	nSelectionLevel = 255
	)			[inherited]

Flood Fill

Parameters:

	xStart,yStart,:	starting point
	cFillColor,:	filling color
	nTolerance,:	deviation from the starting point color
	nOpacity,:	can be from 0 (transparent) to 255 (opaque, default)
	bSelectFilledArea,:	if true, the pixels in the region are also set in the selection layer; default = false
	nSelectionLevel,:	if bSelectFilledArea is true, the selected pixels are set to nSelectionLevel; default = 255 Note: nOpacity=0 && bSelectFilledArea=true act as a "magic wand"

Returns:

true if everything is ok

bool CxImage::Gamma

(

float

gamma

)

[inherited]

Adjusts the color balance of the image

Parameters:

gamma

can be from 0.1 to 5.

Returns:

true if everything is ok

See also:

GammaRGB

bool CxImage::GammaRGB	(	float	gammaR,
		float	gammaG,
		float	gammaB
	)			[inherited]

Adjusts the color balance indipendent for each color channel

Parameters:

gammaR,gammaG,gammaB

can be from 0.1 to 5.

Returns:

true if everything is ok

See also:

Gamma

bool CxImage::GaussianBlur	(	float	radius = 1.0f,
		CxImage *	iDst = 0
	)			[inherited]

Author:

[nipper]; changes [DP]

long CxImage::Histogram	(	long *	red,
		long *	green = 0,
		long *	blue = 0,
		long *	gray = 0,
		long	colorspace = 0
	)			[inherited]

bool CxImage::HistogramEqualize

(

)

[inherited]

bool CxImage::HistogramLog

(

)

[inherited]

bool CxImage::HistogramNormalize

(

)

[inherited]

bool CxImage::HistogramRoot

(

)

[inherited]

bool CxImage::HistogramStretch	(	long	method = 0,
		double	threshold = 0
	)			[inherited]

HistogramStretch

Parameters:

	method,:	0 = luminance (default), 1 = linked channels , 2 = independent channels.
	threshold,:	minimum percentage level in the histogram to recognize it as meaningful. Range: 0.0 to 1.0; default = 0; typical = 0.005 (0.5%);

Returns:

true if everything is ok

Author:

[dave] and [nipper]; changes [DP]

void CxImage::HuePalette

(

float

correction = 1

)

[inherited]

Generates a "rainbow" palette with saturated colors

Parameters:

correction,:

1 generates a single hue spectrum. 0.75 is nice for scientific applications.

bool CxImage::Jitter

(

long

radius = 2

)

[inherited]

Adds a random offset to each pixel in the image

Parameters:

radius,:

maximum pixel displacement

Returns:

true if everything is ok

bool CxImage::Light	(	long	brightness,
		long	contrast = 0
	)			[inherited]

Changes the brightness and the contrast of the image.

Parameters:

	brightness,:	can be from -255 to 255, if brightness is negative, the image becomes dark.
	contrast,:	can be from -100 to 100, the neutral value is 0.

Returns:

true if everything is ok

bool CxImage::Lut	(	BYTE *	pLutR,
		BYTE *	pLutG,
		BYTE *	pLutB,
		BYTE *	pLutA = 0
	)			[inherited]

Apply an indipendent look up table for each channel

Parameters:

pLutR,pLutG,pLutB,pLutA,:

BYTE[256] look up tables

Returns:

true if everything is ok

bool CxImage::Lut

(

BYTE *

pLut

)

[inherited]

Apply a look up table to the image.

Parameters:

pLut,:

BYTE[256] look up table

Returns:

true if everything is ok

float CxImage::Mean

(

)

[inherited]

Returns:

mean lightness of the image. Useful with Threshold() and Light()

bool CxImage::Median

(

long

Ksize = 3

)

[inherited]

Adjusts the intensity of each pixel to the median intensity of its surrounding pixels.

Parameters:

Ksize,:

size of the kernel.

Returns:

true if everything is ok

void CxImage::Mix	(	CxImage &	imgsrc2,
		ImageOpType	op,
		long	lXOffset = 0,
		long	lYOffset = 0,
		bool	bMixAlpha = false
	)			[inherited]

Blends two images

Parameters:

	imgsrc2,:	image to be mixed with this
	op,:	blending method; see ImageOpType
	lXOffset,lYOffset,:	image displacement
	bMixAlpha,:	if true and imgsrc2 has a valid alpha layer, it will be mixed in the destination image.

Returns:

true if everything is ok

thanks to Mwolski

void CxImage::MixFrom	(	CxImage &	imagesrc2,
		long	lXOffset,
		long	lYOffset
	)			[inherited]

bool CxImage::Noise

(

long

level

)

[inherited]

Adds an uniform noise to the image

Parameters:

level,:

can be from 0 (no noise) to 255 (lot of noise).

Returns:

true if everything is ok

int CxImage::OptimalThreshold	(	long	method = 0,
		RECT *	pBox = 0,
		CxImage *	pContrastMask = 0
	)			[inherited]

Finds the optimal (global or local) treshold for image binarization

Parameters:

	method,:	0 = average all methods (default); 1 = Otsu; 2 = Kittler & Illingworth; 3 = max entropy; 4 = potential difference;
	pBox,:	region from where the threshold is computed; 0 = full image (default).
	pContrastMask,:	limit the computation only in regions with contrasted (!=0) pixels; default = 0. the pContrastMask image must be grayscale with same with and height of the current image, can be obtained from the current image with a filter: CxImage iContrastMask(*image,true,false,false); iContrastMask.GrayScale(); long edge[]={-1,-1,-1,-1,8,-1,-1,-1,-1}; iContrastMask.Filter(edge,3,1,0); long blur[]={1,1,1,1,1,1,1,1,1}; iContrastMask.Filter(blur,3,9,0);

Returns:

optimal threshold; -1 = error.

See also:

AdaptiveThreshold

bool CxImage::Repair	(	float	radius = 0.25f,
		long	niterations = 1,
		long	colorspace = 0
	)			[inherited]

Smart blurring to remove small defects, dithering or artifacts.

Parameters:

	radius,:	normally between 0.01 and 0.5
	niterations,:	should be trimmed with radius, to avoid blurring should be (radius*niterations)<1
	colorspace,:	0 = RGB, 1 = HSL, 2 = YUV, 3 = YIQ, 4 = XYZ

Returns:

true if everything is ok

bool CxImage::Saturate	(	const long	saturation,
		const long	colorspace = 1
	)			[inherited]

Changes the saturation of the image.

Parameters:

	saturation,:	can be from -100 to 100, positive values increase the saturation.
	colorspace,:	can be 1 (HSL) or 2 (YUV).

Returns:

true if everything is ok

bool CxImage::SelectiveBlur	(	float	radius = 1.0f,
		BYTE	threshold = 25,
		CxImage *	iDst = 0
	)			[inherited]

Author:

[DP],[nipper]

bool CxImage::ShiftRGB	(	long	r,
		long	g,
		long	b
	)			[inherited]

Adjusts separately the red, green, and blue values in the image.

Parameters:

r,g,b,:

can be from -255 to +255.

Returns:

true if everything is ok

bool CxImage::Solarize	(	BYTE	level = 128,
		bool	bLinkedChannels = true
	)			[inherited]

Solarize: convert all colors above a given lightness level into their negative

Parameters:

	level	: lightness threshold. Range = 0 to 255; default = 128.
	bLinkedChannels,:	true = compare with luminance, preserve colors (default) false = compare with independent R,G,B levels

Returns:

true if everything is ok

Author:

[Priyank Bolia] (priyank_bolia(at)yahoo(dot)com); changes [DP]

bool CxImage::TextBlur	(	BYTE	threshold = 100,
		BYTE	decay = 2,
		BYTE	max_depth = 5,
		bool	bBlurHorizontal = true,
		bool	bBlurVertical = true,
		CxImage *	iDst = 0
	)			[inherited]

Author:

[DP]

bool CxImage::Threshold

(

CxImage *

pThresholdMask

)

[inherited]

Converts the image to B&W, using a threshold mask

Parameters:

pThresholdMask,:

the lightness threshold mask. the pThresholdMask image must be grayscale with same with and height of the current image

Returns:

true if everything is ok

bool CxImage::Threshold

(

BYTE

level

)

[inherited]

Converts the image to B&W. The OptimalThreshold() function can be used for calculating the optimal threshold.

Parameters:

level,:

the lightness threshold.

Returns:

true if everything is ok

bool CxImage::Threshold2	(	BYTE	level,
		bool	bDirection,
		RGBQUAD	nBkgndColor,
		bool	bSetAlpha = false
	)			[inherited]

Filters only the pixels with a lightness less (or more) than the threshold level, and preserves the colors for the unfiltered pixels.

Parameters:

	level	= the lightness threshold.
	bDirection	= false: filter dark pixels, true: filter light pixels
	nBkgndColor	= filtered pixels are set to nBkgndColor color
	bSetAlpha	= if true, sets also the alpha component for the filtered pixels, with nBkgndColor.rgbReserved

Returns:

true if everything is ok

Author:

[DP], [wangsongtao]

bool CxImage::UnsharpMask	(	float	radius = 5.0f,
		float	amount = 0.5f,
		int	threshold = 0
	)			[inherited]

sharpen the image by subtracting a blurred copy from the original image.

Parameters:

	radius,:	width in pixels of the blurring effect. Range: >0; default = 5.
	amount,:	strength of the filter. Range: 0.0 (none) to 1.0 (max); default = 0.5
	threshold,:	difference, between blurred and original pixel, to trigger the filter Range: 0 (always triggered) to 255 (never triggered); default = 0.

Returns:

true if everything is ok

Author:

[nipper]; changes [DP]

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