/*=========================================================================
 *
 *  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 __itkRobustAutomaticThresholdImageFilter_hxx
#define __itkRobustAutomaticThresholdImageFilter_hxx

#include "itkRobustAutomaticThresholdImageFilter.h"
#include "itkBinaryThresholdImageFilter.h"
#include "itkProgressAccumulator.h"

/*
 *
 * This code was contributed in the Insight Journal paper:
 * "Robust Automatic Threshold Selection"
 * by Lehmann G.
 * http://hdl.handle.net/1926/370
 * http://www.insight-journal.org/browse/publication/134
 *
 */

namespace itk
{
template< typename TInputImage, typename TGradientImage, typename TOutputImage >
RobustAutomaticThresholdImageFilter< TInputImage, TGradientImage, TOutputImage >
::RobustAutomaticThresholdImageFilter()
{
  m_OutsideValue   = NumericTraits< OutputPixelType >::Zero;
  m_InsideValue    = NumericTraits< OutputPixelType >::max();
  m_Threshold      = NumericTraits< InputPixelType >::Zero;
  m_Pow = 1;
  this->SetNumberOfRequiredInputs(2);
}

template< typename TInputImage, typename TGradientImage, typename TOutputImage >
void
RobustAutomaticThresholdImageFilter< TInputImage, TGradientImage, TOutputImage >
::GenerateData()
{
  typename ProgressAccumulator::Pointer progress = ProgressAccumulator::New();
  progress->SetMiniPipelineFilter(this);

  // Compute the Threshold for the input image
  typename CalculatorType::Pointer thresholdCalculator = CalculatorType::New();
  thresholdCalculator->SetInput( this->GetInput() );
  thresholdCalculator->SetGradient( this->GetGradientImage() );
  thresholdCalculator->SetPow(m_Pow);
  thresholdCalculator->Compute();

  m_Threshold = thresholdCalculator->GetOutput();

  typename BinaryThresholdImageFilter< TInputImage, TOutputImage >::Pointer threshold =
    BinaryThresholdImageFilter< TInputImage, TOutputImage >::New();

  progress->RegisterInternalFilter(threshold, 1);
  threshold->GraftOutput ( this->GetOutput() );
  threshold->SetInput ( this->GetInput() );
  threshold->SetLowerThreshold(m_Threshold);
  threshold->SetInsideValue (m_InsideValue);
  threshold->SetOutsideValue (m_OutsideValue);
  threshold->Update();

  this->GraftOutput( threshold->GetOutput() );
}

template< typename TInputImage, typename TGradientImage, typename TOutputImage >
void
RobustAutomaticThresholdImageFilter< TInputImage, TGradientImage, TOutputImage >
::GenerateInputRequestedRegion()
{
  const_cast< TInputImage * >( this->GetInput() )->SetRequestedRegionToLargestPossibleRegion();
  const_cast< TGradientImage * >( this->GetGradientImage() )->SetRequestedRegionToLargestPossibleRegion();
}

template< typename TInputImage, typename TGradientImage, typename TOutputImage >
void
RobustAutomaticThresholdImageFilter< TInputImage, TGradientImage, TOutputImage >
::PrintSelf(std::ostream & os, Indent indent) const
{
  Superclass::PrintSelf(os, indent);

  os << indent << "Threshold: " << static_cast< typename NumericTraits< InputPixelType >::PrintType >( m_Threshold )
     << std::endl;
  os << indent << "Pow: " << m_Pow << std::endl;
  os << indent << "OutsideValue: "
     << static_cast< typename NumericTraits< OutputPixelType >::PrintType >( m_OutsideValue ) << std::endl;
  os << indent << "InsideValue: "
     << static_cast< typename NumericTraits< OutputPixelType >::PrintType >( m_InsideValue ) << std::endl;
}
} // end namespace itk
#endif
