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 itkScalarToRGBColormapImageFilter_h
  #define itkScalarToRGBColormapImageFilter_h
  
  #include "itkImageToImageFilter.h"
  
  #include "itkColormapFunction.h"
  
  namespace itk
  {
  /** \class ScalarToRGBColormapImageFilter
   * \brief Implements pixel-wise intensity->rgb mapping operation on one image.
   *
   * This class is parameterized over the type of the input image and
   * the type of the output image.
   *
   * The input image's scalar pixel values are mapped into a color map.
   * The color map is specified by passing the SetColormap function one of the
   * predefined maps. The following selects the "Hot" colormap:
   * \code
   * RGBFilterType::Pointer colormapImageFilter = RGBFilterType::New();
   * colormapImageFilter->SetColormap( RGBFilterType::Hot );
   * \endcode
   *
   * You can also specify a custom color map. This is done by creating
   * a CustomColormapFunction, and then creating lists of values for
   * the red, green, and blue channel. An example of setting the red channel
   * of a colormap with only 2 colors is given below. The blue and green channels
   * should be specified in the same manner.
   *
   * \code
   * // Create the custom colormap
   * typedef itk::Function::CustomColormapFunction<RealImageType::PixelType,
   * RGBImageType::PixelType> ColormapType;
   * ColormapType::Pointer colormap = ColormapType::New();
   * // Setup the red channel of the colormap
   * ColormapType::ChannelType redChannel;
   * redChannel.push_back(0); redChannel.push_back(255);
   * colormap->SetRedChannel( channel );
   * \endcode
   *
   * The range of values present in the input image is the range that is mapped to the entire
   * range of colors.
   *
   * This code was contributed in the Insight Journal paper:
   * "Meeting Andy Warhol Somewhere Over the Rainbow: RGB Colormapping and ITK"
   * by Tustison N., Zhang H., Lehmann G., Yushkevich P., Gee J.
   * https://hdl.handle.net/1926/1452
   * http://www.insight-journal.org/browse/publication/285
   *
   * \sa BinaryFunctionImageFilter TernaryFunctionImageFilter
   *
   * \ingroup   IntensityImageFilters     MultiThreaded
   * \ingroup ITKColormap
   *
   * \wiki
   * \wikiexample{SimpleOperations/ScalarToRGBColormapImageFilter,Apply a color map to an image}
   * \endwiki
   */
  template< typename TInputImage, typename TOutputImage >
  class ScalarToRGBColormapImageFilter:
    public ImageToImageFilter< TInputImage, TOutputImage >
  {
  public:
    /** Standard class typedefs. */
    typedef ScalarToRGBColormapImageFilter                  Self;
    typedef ImageToImageFilter< TInputImage, TOutputImage > 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(ScalarToRGBColormapImageFilter, ImageToImageFilter);
  
    /** Some typedefs. */
    typedef TInputImage                           InputImageType;
    typedef typename InputImageType::ConstPointer InputImagePointer;
    typedef typename InputImageType::RegionType   InputImageRegionType;
    typedef typename InputImageType::PixelType    InputImagePixelType;
    typedef TOutputImage                          OutputImageType;
    typedef typename OutputImageType::Pointer     OutputImagePointer;
    typedef typename OutputImageType::RegionType  OutputImageRegionType;
    typedef typename OutputImageType::PixelType   OutputImagePixelType;
  
    typedef Function::ColormapFunction< InputImagePixelType,
                                      OutputImagePixelType >                                ColormapType;
  
    /**
     * Set/Get the colormap object.
     */
    itkSetObjectMacro(Colormap, ColormapType);
    itkGetModifiableObjectMacro(Colormap, ColormapType);
  
    /**
     * Enum type that provides for an easy interface to existing colormaps.
     */
    typedef enum { Red, Green, Blue, Grey, Hot, Cool, Spring, Summer,
                   Autumn, Winter, Copper, Jet, HSV, OverUnder } ColormapEnumType;
  
    void SetColormap(ColormapEnumType);
  
    /**
     * Set/Get UseInputImageExtremaForScaling.  If 'true', the colormap uses the
     * min and max values from the image to scale appropriately.  Otherwise,
     * these values can be set in the colormap manually.
     */
    itkSetMacro(UseInputImageExtremaForScaling, bool);
    itkGetConstMacro(UseInputImageExtremaForScaling, bool);
    itkBooleanMacro(UseInputImageExtremaForScaling);
  
  protected:
    ScalarToRGBColormapImageFilter();
    virtual ~ScalarToRGBColormapImageFilter() {}
  
    void PrintSelf(std::ostream & os, Indent indent) const ITK_OVERRIDE;
  
    virtual void GenerateOutputInformation() ITK_OVERRIDE
    {
      // this methods is overloaded so that if the output image is a
      // VectorImage then the correct number of components are set.
  
      Superclass::GenerateOutputInformation();
      OutputImageType* output = this->GetOutput();
  
      if ( !output )
        {
        return;
        }
      if ( output->GetNumberOfComponentsPerPixel() != 3 )
        {
        output->SetNumberOfComponentsPerPixel( 3 );
        }
    }
  
    /** ScalarToRGBColormapImageFilter
     * 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 ImageToImageFilter::ThreadedGenerateData(),
     *     ImageToImageFilter::GenerateData()  */
    void ThreadedGenerateData(const OutputImageRegionType & outputRegionForThread,
                              ThreadIdType threadId) ITK_OVERRIDE;
  
    /** Process to execute before entering the multithreaded section */
    void BeforeThreadedGenerateData() ITK_OVERRIDE;
  
  private:
    ScalarToRGBColormapImageFilter(const Self &) ITK_DELETE_FUNCTION;
    void operator=(const Self &) ITK_DELETE_FUNCTION;
  
    typename ColormapType::Pointer m_Colormap;
  
    bool m_UseInputImageExtremaForScaling;
  };
  } // end namespace itk
  
  #ifndef ITK_MANUAL_INSTANTIATION
  #include "itkScalarToRGBColormapImageFilter.hxx"
  #endif
  
  #endif
  