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/*=========================================================================
*
* Copyright Insight Software Consortium
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0.txt
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*=========================================================================*/
#ifndef itkNarrowBandCurvesLevelSetImageFilter_h
#define itkNarrowBandCurvesLevelSetImageFilter_h
#include "itkNarrowBandLevelSetImageFilter.h"
#include "itkCurvesLevelSetFunction.h"
namespace itk
{
/** \class NarrowBandCurvesLevelSetImageFilter
* \brief Segments structures in images based on user supplied edge potential map.
*
* \par IMPORTANT
* The NarrowBandLevelSetImageFilter class and the
* CurvesLevelSetFunction class contain additional information necessary
* to the full understanding of how to use this filter.
*
* \par OVERVIEW
* This class is a level set method segmentation filter. An initial contour
* is propagated outwards (or inwards) until it sticks to the shape boundaries.
* This is done by using a level set speed function based on a user supplied
* edge potential map.
*
* \par INPUTS
* This filter requires two inputs. The first input is a initial level set.
* The initial level set is a real image which contains the initial contour/surface
* as the zero level set. For example, a signed distance function from the initial
* contour/surface is typically used. Unlike the simpler ShapeDetectionLevelSetImageFilter
* the initial contour does not have to lie wholly within the shape to be segmented.
* The initial contour is allow to overlap the shape boundary. The extra advection term
* in the update equation behaves like a doublet and attracts the contour to the boundary.
* This approach for segmentation follows that of Lorigo et al (2001).
*
* \par
* The second input is the feature image. For this filter, this is the edge
* potential map. General characteristics of an edge potential map is that
* it has values close to zero in regions near the edges and values close
* to one inside the shape itself. Typically, the edge potential map is compute
* from the image gradient, for example:
*
* \f[ g(I) = 1 / ( 1 + | (\nabla * G)(I)| ) \f]
* \f[ g(I) = \exp^{-|(\nabla * G)(I)|} \f]
*
* where \f$ I \f$ is image intensity and
* \f$ (\nabla * G) \f$ is the derivative of Gaussian operator.
*
* \par
* See NarrowBandLevelSetImageFilter and NarrowBandImageFilterBase
* for more information on Inputs.
*
* \par PARAMETERS
* The method SetUseNegatiiveFeatures() can be used to switch from propagating inwards (false)
* versus propagting outwards (true).
*
* This implementation allows the user to set the weights between the propagation, advection
* and curvature term using methods SetPropagationScaling(), SetAdvectionScaling(),
* SetCurvatureScaling(). In general, the larger the CurvatureScaling, the smoother the
* resulting contour. To follow the implementation in Caselles's paper,
* set the PropagationScaling to \f$ c \f$ (the inflation or ballon force) and
* AdvectionScaling and CurvatureScaling both to 1.0.
*
* \par OUTPUTS
* The filter outputs a single, scalar, real-valued image.
* Negative values in the output image are inside the segmentated region
* and positive values in the image are outside of the inside region. The
* zero crossings of the image correspond to the position of the level set
* front.
*
* \par REFERENCES
* L. Lorigo, O. Faugeras, W.E.L. Grimson, R. Keriven, R. Kikinis, A. Nabavi,
* and C.-F. Westin, Curves: Curve evolution for vessel segmentation.
* Medical Image Analysis, 5:195-206, 2001.
*
* \par
* See NarrowBandImageFilterBase and
* NarrowBandLevelSetImageFilter for more information.
*
* \sa NarrowBandLevelSetImageFilter
* \sa CurvesLevelSetFunction
*
* \ingroup LevelSetSegmentation
* \ingroup ITKLevelSets
*/
template< typename TInputImage,
typename TFeatureImage,
typename TOutputPixelType = float >
class NarrowBandCurvesLevelSetImageFilter:
public NarrowBandLevelSetImageFilter< TInputImage, TFeatureImage, TOutputPixelType,
Image< TOutputPixelType,
TInputImage::ImageDimension > >
{
public:
/** Standard class typedefs */
typedef NarrowBandCurvesLevelSetImageFilter Self;
typedef NarrowBandLevelSetImageFilter< TInputImage, TFeatureImage, TOutputPixelType,
Image< TOutputPixelType,
TInputImage::ImageDimension > >
Superclass;
typedef SmartPointer< Self > Pointer;
typedef SmartPointer< const Self > ConstPointer;
/** Inherited typedef from the superclass. */
typedef typename Superclass::ValueType ValueType;
typedef typename Superclass::OutputImageType OutputImageType;
typedef typename Superclass::FeatureImageType FeatureImageType;
/** Type of the segmentation function */
typedef CurvesLevelSetFunction< OutputImageType,
FeatureImageType > CurvesFunctionType;
typedef typename CurvesFunctionType::Pointer
CurvesFunctionPointer;
/** Run-time type information (and related methods). */
itkTypeMacro(NarrowBandCurvesLevelSetImageFilter, NarrowBandLevelSetImageFilter);
/** Method for creation through the object factory */
itkNewMacro(Self);
/** Set the value of sigma used to compute derivatives */
void SetDerivativeSigma(float value)
{
m_CurvesFunction->SetDerivativeSigma(value);
this->Modified();
}
float GetDerivativeSigma() const
{ return m_CurvesFunction->GetDerivativeSigma(); }
#ifdef ITK_USE_CONCEPT_CHECKING
// Begin concept checking
itkConceptMacro( OutputHasNumericTraitsCheck,
( Concept::HasNumericTraits< TOutputPixelType > ) );
// End concept checking
#endif
protected:
~NarrowBandCurvesLevelSetImageFilter() {}
NarrowBandCurvesLevelSetImageFilter();
virtual void PrintSelf(std::ostream & os, Indent indent) const ITK_OVERRIDE;
NarrowBandCurvesLevelSetImageFilter(const Self &) ITK_DELETE_FUNCTION;
void operator=(const Self &) ITK_DELETE_FUNCTION;
/** Overridden from Superclass to handle the case when Propagation
* Scaling is zero.*/
void GenerateData() ITK_OVERRIDE;
private:
CurvesFunctionPointer m_CurvesFunction;
};
} // end namespace itk
#ifndef ITK_MANUAL_INSTANTIATION
#include "itkNarrowBandCurvesLevelSetImageFilter.hxx"
#endif
#endif
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