// -------------------------------------------------------------------------
// @author Leonardo Florez-Valencia (florez-l@javeriana.edu.co)
// -------------------------------------------------------------------------

#ifndef __CPEXTENSIONS__ALGORITHMS__REGIONOFINTERESTIMAGECALCULATOR__HXX__
#define __CPEXTENSIONS__ALGORITHMS__REGIONOFINTERESTIMAGECALCULATOR__HXX__

#include <itkImageRegionConstIteratorWithIndex.h>

// -------------------------------------------------------------------------
template< class _TImage >
void cpExtensions::Algorithms::RegionOfInterestImageCalculator< _TImage >::
Compute( )
{
  typedef itk::ImageRegionConstIteratorWithIndex< _TImage > _TIterator;
  typedef typename _TImage::RegionType _TRegion;

  if( this->m_Image.IsNotNull( ) )
  {
    _TRegion region = this->m_Image->GetRequestedRegion( );
    TIndex minidx = region.GetIndex( );
    TIndex maxidx = minidx + region.GetSize( );
    for( unsigned int d = 0; d < _TImage::ImageDimension; ++d )
      maxidx[ d ] -= 1;

    bool first = true;
    _TIterator i( this->m_Image, region );
    for( i.GoToBegin( ); !i.IsAtEnd( ); ++i )
    {
      if( i.Get( ) != this->m_BackgroundValue )
      {
        TIndex idx = i.GetIndex( );
        if( !first )
        {
          for( unsigned int d = 0; d < _TImage::ImageDimension; ++d )
          {
            minidx[ d ] = ( idx[ d ] < minidx[ d ] )? idx[ d ]: minidx[ d ];
            maxidx[ d ] = ( idx[ d ] > maxidx[ d ] )? idx[ d ]: maxidx[ d ];

          } // rof
        }
        else
        {
          minidx = maxidx = idx;
          first = false;

        } // fi

      } // fi

    } // rof
    this->m_Minimum = minidx;
    this->m_Maximum = maxidx;
  }
  else
  {
    this->m_Minimum.Fill( 0 );
    this->m_Maximum.Fill( 0 );

  } // fi
}
      
// -------------------------------------------------------------------------
template< class _TImage >
cpExtensions::Algorithms::RegionOfInterestImageCalculator< _TImage >::
RegionOfInterestImageCalculator( )
  : Superclass( ),
    m_BackgroundValue( TPixel( 0 ) )
{
  this->m_Minimum.Fill( 0 );
  this->m_Maximum.Fill( 0 );
}

// -------------------------------------------------------------------------
template< class _TImage >
cpExtensions::Algorithms::RegionOfInterestImageCalculator< _TImage >::
~RegionOfInterestImageCalculator( )
{
}


/* TODO
   typename _TImage::ConstPointer m_Image;
   TPixel m_BackgroundValue;
   TIndex m_Minimum;
   TIndex m_Maximum;
   };
*/

#endif // __CPEXTENSIONS__ALGORITHMS__REGIONOFINTERESTIMAGECALCULATOR__HXX__

// eof - $RCSfile$