text: /*=========================================================================
   *
   *  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 __itkNoiseImageFilter_h
  #define __itkNoiseImageFilter_h
  
  #include "itkBoxImageFilter.h"
  #include "itkImage.h"
  #include "itkNumericTraits.h"
  
  namespace itk
  {
  /** \class NoiseImageFilter
   * \brief Calculate the local noise in an image.
   *
   * Computes an image where a given pixel is the standard deviation of
   * the pixels in a neighborhood about the corresponding input pixel.
   * This serves as an estimate of the local noise (or texture) in an
   * image. Currently, this noise estimate assume a piecewise constant
   * image.  This filter should be extended to fitting a (hyper) plane
   * to the neighborhood and calculating the standard deviation of the
   * residuals to this (hyper) plane.
   *
   * \sa Image
   * \sa Neighborhood
   * \sa NeighborhoodOperator
   * \sa NeighborhoodIterator
   *
   * \ingroup IntensityImageFilters
   * \ingroup ITKImageFilterBase
   *
   * \wiki
   * \wikiexample{Statistics/NoiseImageFilter,Compute the local noise in an image}
   * \endwiki
   */
  template< class TInputImage, class TOutputImage >
  class ITK_EXPORT NoiseImageFilter:
    public BoxImageFilter< TInputImage, TOutputImage >
  {
  public:
    /** Extract dimension from input and output image. */
    itkStaticConstMacro(InputImageDimension, unsigned int,
                        TInputImage::ImageDimension);
    itkStaticConstMacro(OutputImageDimension, unsigned int,
                        TOutputImage::ImageDimension);
  
    /** Convenient typedefs for simplifying declarations. */
    typedef TInputImage  InputImageType;
    typedef TOutputImage OutputImageType;
  
    /** Standard class typedefs. */
    typedef NoiseImageFilter                                  Self;
    typedef BoxImageFilter< InputImageType, OutputImageType > Superclass;
    typedef SmartPointer< Self >                              Pointer;
    typedef SmartPointer< const Self >                        ConstPointer;
  
    /** Method for creation through the object factory. */
    itkNewMacro(Self);
  
    /** Run-time type information (and related methods). */
    itkTypeMacro(NoiseImageFilter, BoxImageFilter);
  
    /** Image typedef support. */
    typedef typename InputImageType::PixelType                 InputPixelType;
    typedef typename OutputImageType::PixelType                OutputPixelType;
    typedef typename NumericTraits< InputPixelType >::RealType InputRealType;
  
    typedef typename InputImageType::RegionType  InputImageRegionType;
    typedef typename OutputImageType::RegionType OutputImageRegionType;
  
    typedef typename InputImageType::SizeType InputSizeType;
  
  #ifdef ITK_USE_CONCEPT_CHECKING
    /** Begin concept checking */
    itkConceptMacro( InputHasNumericTraitsCheck,
                     ( Concept::HasNumericTraits< InputPixelType > ) );
    /** End concept checking */
  #endif
  protected:
    NoiseImageFilter();
    virtual ~NoiseImageFilter() {}
  
    /** NoiseImageFilter can be implemented as a multithreaded filter.
     * Therefore, this implementation provides a ThreadedGenerateData()
     * routine which is called for each processing thread. The output
     * image data is allocated automatically by the superclass prior to
     * calling ThreadedGenerateData().  ThreadedGenerateData can only
     * write to the portion of the output image specified by the
     * parameter "outputRegionForThread"
     *
     * \sa BoxImageFilter::ThreadedGenerateData(),
     *     BoxImageFilter::GenerateData() */
    void ThreadedGenerateData(const OutputImageRegionType & outputRegionForThread,
                              ThreadIdType threadId);
  
  private:
    NoiseImageFilter(const Self &); //purposely not implemented
    void operator=(const Self &);   //purposely not implemented
  };
  } // end namespace itk
  
  #ifndef ITK_MANUAL_INSTANTIATION
  #include "itkNoiseImageFilter.hxx"
  #endif
  
  #endif
  