Variational Stationary Noise Remover. More...

IPSDKIPLFILTERING_API VSNRResult	ipsdk::imaproc::filter::vsnr2dImg (const image::ImageConstPtr &pInImg, const ipUInt32 nbIter, const ipReal32 stdDevX, const ipReal32 stdDevY, const ipReal32 theta, const ipReal64 alpha)
	wrapper function for Variational Stationary Noise Remover More...

IPSDKIPLFILTERING_API void	ipsdk::imaproc::filter::vsnr2dImg (const image::ImageConstPtr &pInImg, const ipUInt32 nbIter, const ipReal32 stdDevX, const ipReal32 stdDevY, const ipReal32 theta, const ipReal64 alpha, const image::ImagePtr &pOutCorrectedImg, const image::ImagePtr &pOutNoiseImg)
	wrapper function for Variational Stationary Noise Remover More...

IPSDKIPLFILTERING_API VSNRResult	ipsdk::imaproc::filter::vsnr2dImg (const image::ImageConstPtr &pInImg, const image::ImageConstPtr &pNoiseImg, const ipUInt32 nbIter, const ipReal64 alpha)
	wrapper function for Variational Stationary Noise Remover More...

IPSDKIPLFILTERING_API void	ipsdk::imaproc::filter::vsnr2dImg (const image::ImageConstPtr &pInImg, const image::ImageConstPtr &pNoiseImg, const ipUInt32 nbIter, const ipReal64 alpha, const image::ImagePtr &pOutCorrectedImg, const image::ImagePtr &pOutNoiseImg)
	wrapper function for Variational Stationary Noise Remover More...

Detailed Description

Variational Stationary Noise Remover.

Standard denoising methods rely on a white noise assumption. This means that the intensity alteration is spatially uncorrelated. The VSNR (Variational Stationary Noise Remover) algorithm removes structural noise, i.e. following a pattern, in the input image [1].

In a generic case, we can express the noisy image $I$ as the sum of the clean image $I_0$ and the noise image $I_N$ :

$I = I_0 + I_N$

In the case of stationary noise $I_N$ can be expressed as the convolution of white noise $\lambda$ with a pattern $\psi$ :

$I_N = \sum_{i=1}^{n}{ \lambda_i * \psi_i}$

where $ * $ is the convolution operator.

In this IPSDK implementation, noise the pattern $\psi$ can be provided as an input image or can be expressed as an oriented Gabor function, by providing the Gabor parameters:

$g(x, y) = \exp \left( -\frac{x'^2}{2 \sigma_x^2} - \frac{y'^2}{2 \sigma_y^2} \right)$

Where $ (x', y') $ are the coordinates after a rotation of $\theta$ :

$x' = x \cos( \theta ) + y \sin( \theta )$

$y' = -x \sin( \theta ) + y \cos( \theta )$

Note: In the case of parametrized Gabor pattern, the input parameter InTheta is expressed in degrees.

This is an example of noie image according $I_N$ to a Gabor pattern $\psi$ with an orientation of 45° and a white noise $\lambda$ :

The noise image estimation can be estimated by iteratively solving the following optimization problem:

$P(\lambda) = \left\| \nabla \left( I_N - \sum_{i=1}^{m}{\lambda_i * \psi_i} \right) \right\|_{1, \epsilon} + \sum_{i=1}^{m}{\phi(\lambda_i)}$

Where $\phi(\lambda)$ is the regularization term.

Please, see [1] for more details.

Here is an example of VSNR filtering result:

[1] Variational algorithms to remove stationary noise. Application to microscopy imaging. J. Fehrenbach, P. Weiss and C. Lorenzo, IEEE Image Processing Vol. 21, Issue 10, pages 4420 - 4430, October (2012)

Attributes description

Attribute description for algorithm :

Name	ToolTip	Default Initializer
ipsdk::imaproc::attr::InImg	[Input] image for processing operation	X
ipsdk::imaproc::attr::InOptImg1	[Input Optional] first input image for operation	X
ipsdk::imaproc::attr::InNbIter	[Input] Number of iterations for an iterative algorithm	X
ipsdk::imaproc::attr::InOptGaborParams	[Input Optional] Parameters to generate a Gabor signal	X
ipsdk::imaproc::attr::InFactor	[Input] Multiplying factor. Used for instance by shading correction algorithm	X
ipsdk::imaproc::attr::OutOptWk1Img	[Output Optional] Temporary working image for algorithm	X
ipsdk::imaproc::attr::OutWk1RealImg	[Output] Temporary working image for algorithm	ipsdk::imaproc::duplicateInOut (_pOutWk1RealImg, _pInImg, ipsdk::image::eImageBufferType::eIBT_Real32)
ipsdk::imaproc::attr::OutWk2RealImg	[Output] Temporary working image for algorithm	ipsdk::imaproc::duplicateInOut (_pOutWk2RealImg, _pInImg, ipsdk::image::eImageBufferType::eIBT_Real32)
ipsdk::imaproc::attr::OutWk3RealImg	[Output] Temporary working image for algorithm	ipsdk::imaproc::duplicateInOut (_pOutWk3RealImg, _pInImg, ipsdk::image::eImageBufferType::eIBT_Real32)
ipsdk::imaproc::attr::OutWk4RealImg	[Output] Temporary working image for algorithm	ipsdk::imaproc::duplicateInOut (_pOutWk4RealImg, _pInImg, ipsdk::image::eImageBufferType::eIBT_Real32)
ipsdk::imaproc::attr::OutWk5RealImg	[Output] Temporary working image for algorithm	ipsdk::imaproc::duplicateInOut (_pOutWk5RealImg, _pInImg, ipsdk::image::eImageBufferType::eIBT_Real32)
ipsdk::imaproc::attr::OutWk6RealImg	[Output] Temporary working image for algorithm	ipsdk::imaproc::duplicateInOut (_pOutWk6RealImg, _pInImg, ipsdk::image::eImageBufferType::eIBT_Real32)
ipsdk::imaproc::attr::OutWk7RealImg	[Output] Temporary working image for algorithm	ipsdk::imaproc::duplicateInOut (_pOutWk7RealImg, _pInImg, ipsdk::image::eImageBufferType::eIBT_Real32)
ipsdk::imaproc::attr::OutWk8RealImg	[Output] Temporary working image for algorithm	ipsdk::imaproc::duplicateInOut (_pOutWk8RealImg, _pInImg, ipsdk::image::eImageBufferType::eIBT_Real32)
ipsdk::imaproc::attr::OutWk9RealImg	[Output] Temporary working image for algorithm	ipsdk::imaproc::duplicateInOut (_pOutWk9RealImg, _pInImg, ipsdk::image::eImageBufferType::eIBT_Real32)
ipsdk::imaproc::attr::OutWk10RealImg	[Output] Temporary working image for algorithm	ipsdk::imaproc::duplicateInOut (_pOutWk10RealImg, _pInImg, ipsdk::image::eImageBufferType::eIBT_Real32)
ipsdk::imaproc::attr::OutWk11RealImg	[Output] Temporary working image for algorithm	ipsdk::imaproc::duplicateInOut (_pOutWk11RealImg, _pInImg, ipsdk::image::eImageBufferType::eIBT_Real32)
ipsdk::imaproc::attr::OutWk12RealImg	[Output] Temporary working image for algorithm	ipsdk::imaproc::duplicateInOut (_pOutWk12RealImg, _pInImg, ipsdk::image::eImageBufferType::eIBT_Real32)
ipsdk::imaproc::attr::OutWk13RealImg	[Output] Temporary working image for algorithm	ipsdk::imaproc::duplicateInOut (_pOutWk13RealImg, _pInImg, ipsdk::image::eImageBufferType::eIBT_Real32)
ipsdk::imaproc::attr::OutWk14RealImg	[Output] Temporary working image for algorithm	ipsdk::imaproc::duplicateInOut (_pOutWk14RealImg, _pInImg, ipsdk::image::eImageBufferType::eIBT_Real32)
ipsdk::imaproc::attr::OutWk15RealImg	[Output] Temporary working image for algorithm	ipsdk::imaproc::duplicateInOut (_pOutWk15RealImg, _pInImg, ipsdk::image::eImageBufferType::eIBT_Real32)
ipsdk::imaproc::attr::OutWk16RealImg	[Output] Temporary working image for algorithm	ipsdk::imaproc::duplicateInOut (_pOutWk16RealImg, _pInImg, ipsdk::image::eImageBufferType::eIBT_Real32)
ipsdk::imaproc::attr::OutWk17RealImg	[Output] Temporary working image for algorithm	ipsdk::imaproc::duplicateInOut (_pOutWk17RealImg, _pInImg, ipsdk::image::eImageBufferType::eIBT_Real32)
ipsdk::imaproc::attr::OutWk18RealImg	[Output] Temporary working image for algorithm	ipsdk::imaproc::duplicateInOut (_pOutWk18RealImg, _pInImg, ipsdk::image::eImageBufferType::eIBT_Real32)
ipsdk::imaproc::attr::OutWk19RealImg	[Output] Temporary working image for algorithm	ipsdk::imaproc::duplicateInOut (_pOutWk19RealImg, _pInImg, ipsdk::image::eImageBufferType::eIBT_Real32)
ipsdk::imaproc::attr::OutWk20RealImg	[Output] Temporary working image for algorithm	ipsdk::imaproc::duplicateInOut (_pOutWk20RealImg, _pInImg, ipsdk::image::eImageBufferType::eIBT_Real32)
ipsdk::imaproc::attr::OutWk21RealImg	[Output] Temporary working image for algorithm	ipsdk::imaproc::duplicateInOut (_pOutWk21RealImg, _pInImg, ipsdk::image::eImageBufferType::eIBT_Real32)
ipsdk::imaproc::attr::OutWk22RealImg	[Output] Temporary working image for algorithm	ipsdk::imaproc::duplicateInOut (_pOutWk22RealImg, _pInImg, ipsdk::image::eImageBufferType::eIBT_Real32)
ipsdk::imaproc::attr::OutImg1	[Output] First output image	ipsdk::imaproc::duplicateInOut (_pOutImg1, _pInImg, ipsdk::image::eImageBufferType::eIBT_Real32)
ipsdk::imaproc::attr::OutImg2	[Output] Second output image	ipsdk::imaproc::duplicateInOut (_pOutImg2, _pInImg, ipsdk::image::eImageBufferType::eIBT_Real32)

Global Rule description

Global rule description for algorithm :
ipsdk::imaproc::matchSize (_pInImg,_pOutImg1) &&
ipsdk::imaproc::matchSize (_pInImg,_pOutImg2) &&
ipsdk::imaproc::matchSize (_pInImg,_pOutWk1RealImg) &&
ipsdk::imaproc::matchSize (_pInImg,_pOutWk2RealImg) &&
ipsdk::imaproc::matchSize (_pInImg,_pOutWk3RealImg) &&
ipsdk::imaproc::matchSize (_pInImg,_pOutWk4RealImg) &&
ipsdk::imaproc::matchSize (_pInImg,_pOutWk5RealImg) &&
ipsdk::imaproc::matchSize (_pInImg,_pOutWk6RealImg) &&
ipsdk::imaproc::matchSize (_pInImg,_pOutWk7RealImg) &&
ipsdk::imaproc::matchSize (_pInImg,_pOutWk8RealImg) &&
ipsdk::imaproc::matchSize (_pInImg,_pOutWk9RealImg) &&
ipsdk::imaproc::matchSize (_pInImg,_pOutWk10RealImg) &&
ipsdk::imaproc::matchSize (_pInImg,_pOutWk11RealImg) &&
ipsdk::imaproc::matchSize (_pInImg,_pOutWk12RealImg) &&
ipsdk::imaproc::matchSize (_pInImg,_pOutWk13RealImg) &&
ipsdk::imaproc::matchSize (_pInImg,_pOutWk14RealImg) &&
ipsdk::imaproc::matchSize (_pInImg,_pOutWk15RealImg) &&
ipsdk::imaproc::matchSize (_pInImg,_pOutWk16RealImg) &&
ipsdk::imaproc::matchSize (_pInImg,_pOutWk17RealImg) &&
ipsdk::imaproc::matchSize (_pInImg,_pOutWk18RealImg) &&
ipsdk::imaproc::matchSize (_pInImg,_pOutWk19RealImg) &&
ipsdk::imaproc::matchSize (_pInImg,_pOutWk20RealImg) &&
ipsdk::imaproc::matchSize (_pInImg,_pOutWk21RealImg) &&
ipsdk::imaproc::matchSize (_pInImg,_pOutWk22RealImg) &&
ipsdk::processor::ifIsSet (_pInOptImg1,
ipsdk::imaproc::matchSize (_pInImg,_pInOptImg1))

Example of Python code :

Example imports

import PyIPSDK

import PyIPSDK.IPSDKIPLFiltering as filter

Code Example

    # opening of input images
    inImg = PyIPSDK.loadTiffImageFile(inputImgPath)
    
    # unsharp mask 2d computation
    outImg, noiseImg = filter.vsnr2dImg(inImg, 12, 1, 30, 0, 1)

Example of C++ code :

Example informations

Associated library

IPSDKIPLFiltering

Header file

#include <IPSDKIPL/IPSDKIPLFiltering/Processor/VSNR2dImg/VSNR2dImg.h>

Code Example

// compute median on input image

VSNRResult result = vsnr2dImg(pInImg, 12, 1.f, 30.f, 0.f, 1.f);

See also: VSNR2dImgLvl1

Function Documentation

◆ vsnr2dImg() [1/4]

IPSDKIPLFILTERING_API VSNRResult ipsdk::imaproc::filter::vsnr2dImg	(	const image::ImageConstPtr &	pInImg,
		const ipUInt32	nbIter,
		const ipReal32	stdDevX,
		const ipReal32	stdDevY,
		const ipReal32	theta,
		const ipReal64	alpha
	)

wrapper function for Variational Stationary Noise Remover

Exceptions

ipsdk::processor::IPSDKBaseProcessingException on failure

◆ vsnr2dImg() [2/4]

IPSDKIPLFILTERING_API void ipsdk::imaproc::filter::vsnr2dImg	(	const image::ImageConstPtr &	pInImg,
		const ipUInt32	nbIter,
		const ipReal32	stdDevX,
		const ipReal32	stdDevY,
		const ipReal32	theta,
		const ipReal64	alpha,
		const image::ImagePtr &	pOutCorrectedImg,
		const image::ImagePtr &	pOutNoiseImg
	)

wrapper function for Variational Stationary Noise Remover

Exceptions

ipsdk::processor::IPSDKBaseProcessingException on failure

◆ vsnr2dImg() [3/4]

IPSDKIPLFILTERING_API VSNRResult ipsdk::imaproc::filter::vsnr2dImg	(	const image::ImageConstPtr &	pInImg,
		const image::ImageConstPtr &	pNoiseImg,
		const ipUInt32	nbIter,
		const ipReal64	alpha
	)

wrapper function for Variational Stationary Noise Remover

Exceptions

ipsdk::processor::IPSDKBaseProcessingException on failure

◆ vsnr2dImg() [4/4]

IPSDKIPLFILTERING_API void ipsdk::imaproc::filter::vsnr2dImg	(	const image::ImageConstPtr &	pInImg,
		const image::ImageConstPtr &	pNoiseImg,
		const ipUInt32	nbIter,
		const ipReal64	alpha,
		const image::ImagePtr &	pOutCorrectedImg,
		const image::ImagePtr &	pOutNoiseImg
	)

wrapper function for Variational Stationary Noise Remover

Exceptions

ipsdk::processor::IPSDKBaseProcessingException on failure