Primitives for computing the stansdard deviation of the integral images. More...

RectStdDev
NppStatus	nppiRectStdDev_32f_C1R (const Npp32f pSrc, int nSrcStep, const Npp64f pSqr, int nSqrStep, Npp32f *pDst, int nDstStep, NppiSize oSizeROI, NppiRect oRect)
	One-channel 32-bit floating point image RectStdDev. More...

NppStatus	nppiRectStdDev_32s_C1RSfs (const Npp32s pSrc, int nSrcStep, const Npp32s pSqr, int nSqrStep, Npp32s *pDst, int nDstStep, NppiSize oSizeROI, NppiRect oRect, int nScaleFactor)
	One-channel 32-bit signed image RectStdDev, scaled by . More...

NppStatus	nppiRectStdDev_32s32f_C1R (const Npp32s pSrc, int nSrcStep, const Npp64f pSqr, int nSqrStep, Npp32f *pDst, int nDstStep, NppiSize oSizeROI, NppiRect oRect)
	One-channel 32-bit signed image RectStdDev. More...

Detailed Description

Primitives for computing the stansdard deviation of the integral images.

The function computes the standard deviation of the pixel in the rectangular window with the integral image $pSrc$ and the squared integral image $pSqr$ , which can be obtained by calling Integral and SqrIntegral.

The standard deviation of the pixel $(j, i)$ can be computed using the formula:

$pDst(j, i) = \sqrt{max(0, \frac{\sum(SqrIntegral)\cdot N - (\sum(Integral))^2}{N^2})}$

where $\sum(SqrIntegral) = pSqr[j+oRect.y+oRect.height, i+oRect.x+oRect.width] - pSqr[j+oRect.y,i+oRect.x+oRect.width] - pSqr[j+oRect.y+oRect.height, i+oRect.x] + pSqr[j+oRect.y, i+oRect.x]$ , $\sum(Integral) = pSrc[j+oRect.y+oRect.height, i+oRect.x+oRect.width] - pSrc[j+oRect.y,i+oRect.x+oRect.width] - pSrc[j+oRect.y+oRect.height, i+oRect.x] + pSrc[j+oRect.y, i+oRect.x]$ , $N = oRect.width \cdot oRect.height$ .

The size of the $pSrc$ and $pSqr$ should be $(oSizeROI.width + oRect.x + oRect.width, oSizeROI.height + oRect.y + oRect.height).$

Function Documentation

NppStatus nppiRectStdDev_32f_C1R	(	const Npp32f *	pSrc,
		int	nSrcStep,
		const Npp64f *	pSqr,
		int	nSqrStep,
		Npp32f *	pDst,
		int	nDstStep,
		NppiSize	oSizeROI,
		NppiRect	oRect
	)

One-channel 32-bit floating point image RectStdDev.

Parameters

pSrc	Source-Image Pointer.
nSrcStep	Source-Image Line Step.
pSqr	Destination-Image Pointer.
nSqrStep	Destination-Image Line Step.
pDst	Destination-Image Pointer.
nDstStep	Destination-Image Line Step.
oSizeROI	Region-of-Interest (ROI).
oRect	rectangular window

Returns: Image Data Related Error Codes, ROI Related Error Codes

NppStatus nppiRectStdDev_32s32f_C1R	(	const Npp32s *	pSrc,
		int	nSrcStep,
		const Npp64f *	pSqr,
		int	nSqrStep,
		Npp32f *	pDst,
		int	nDstStep,
		NppiSize	oSizeROI,
		NppiRect	oRect
	)

One-channel 32-bit signed image RectStdDev.

Parameters

pSrc	Source-Image Pointer.
nSrcStep	Source-Image Line Step.
pSqr	Destination-Image Pointer.
nSqrStep	Destination-Image Line Step.
pDst	Destination-Image Pointer.
nDstStep	Destination-Image Line Step.
oSizeROI	Region-of-Interest (ROI).
oRect	rectangular window

Returns: Image Data Related Error Codes, ROI Related Error Codes

NppStatus nppiRectStdDev_32s_C1RSfs	(	const Npp32s *	pSrc,
		int	nSrcStep,
		const Npp32s *	pSqr,
		int	nSqrStep,
		Npp32s *	pDst,
		int	nDstStep,
		NppiSize	oSizeROI,
		NppiRect	oRect,
		int	nScaleFactor
	)

One-channel 32-bit signed image RectStdDev, scaled by $2^(-nScaleFactor)$ .

Parameters

pSrc	Source-Image Pointer.
nSrcStep	Source-Image Line Step.
pSqr	Destination-Image Pointer.
nSqrStep	Destination-Image Line Step.
pDst	Destination-Image Pointer.
nDstStep	Destination-Image Line Step.
oSizeROI	Region-of-Interest (ROI).
oRect	rectangular window
nScaleFactor	Integer Result Scaling.

Returns: Image Data Related Error Codes, ROI Related Error Codes