1 #ifndef __fpa__Image__SkeletonFilter__hxx__
2 #define __fpa__Image__SkeletonFilter__hxx__
4 #include <fpa/Base/Functors/Inverse.h>
5 #include <fpa/Image/Functors/SimpleNeighborhood.h>
6 #include <itkImageRegionIteratorWithIndex.h>
8 // -------------------------------------------------------------------------
9 #define fpa_Image_SkeletonFilter_OutputMacro( o_n, o_t ) \
10 template< class _TImage > \
11 typename fpa::Image::SkeletonFilter< _TImage >:: \
12 o_t* fpa::Image::SkeletonFilter< _TImage >:: \
16 dynamic_cast< o_t* >( \
17 this->itk::ProcessObject::GetOutput( this->m_##o_n##Idx ) \
22 fpa_Image_SkeletonFilter_OutputMacro( Skeleton, TSkeleton );
23 fpa_Image_SkeletonFilter_OutputMacro( Marks, TMarks );
25 // -------------------------------------------------------------------------
26 template< class _TImage >
27 fpa::Image::SkeletonFilter< _TImage >::
31 typedef typename _TImage::PixelType _TPixel;
32 typedef fpa::Image::Functors::SimpleNeighborhood< _TImage::ImageDimension > _TNeighFunc;
33 typedef fpa::Base::Functors::Inverse< _TPixel, _TPixel > _TInvFunc;
35 unsigned int nOutputs = this->GetNumberOfRequiredOutputs( );
36 this->SetNumberOfRequiredOutputs( nOutputs + 2 );
37 this->m_SkeletonIdx = nOutputs;
38 this->m_MarksIdx = nOutputs + 1;
40 typename TSkeleton::Pointer skeleton = TSkeleton::New( );
41 typename TMarks::Pointer marks = TMarks::New( );
42 this->SetNthOutput( this->m_SkeletonIdx, skeleton.GetPointer( ) );
43 this->SetNthOutput( this->m_MarksIdx, marks.GetPointer( ) );
45 typename _TNeighFunc::Pointer nfunc = _TNeighFunc::New( );
47 this->SetNeighborhoodFunction( nfunc );
49 typename _TInvFunc::Pointer ifunc = _TInvFunc::New( );
50 this->SetConversionFunction( ifunc );
53 // -------------------------------------------------------------------------
54 template< class _TImage >
55 fpa::Image::SkeletonFilter< _TImage >::
60 // -------------------------------------------------------------------------
61 template< class _TImage >
62 void fpa::Image::SkeletonFilter< _TImage >::
63 _BeforeGenerateData( )
65 this->Superclass::_BeforeGenerateData( );
66 this->m_SkeletonQueue.clear( );
69 // -------------------------------------------------------------------------
70 template< class _TImage >
71 void fpa::Image::SkeletonFilter< _TImage >::
72 _UpdateResult( const _TQueueNode& n )
74 typedef typename _TSkeletonQueue::value_type _TSkeletonQueueValue;
76 this->Superclass::_UpdateResult( n );
77 double d = double( this->GetInput( )->GetPixel( n.Vertex ) );
78 if( d >= double( 0 ) )
80 // Update skeleton candidates
82 double v = double( n.Result ) / ( d * d );
83 this->m_SkeletonQueue.insert( _TSkeletonQueueValue( v, n.Vertex ) );
88 // -------------------------------------------------------------------------
89 template< class _TImage >
90 void fpa::Image::SkeletonFilter< _TImage >::
93 this->Superclass::_AfterGenerateData( );
96 std::vector< TIndex > end_points;
97 this->_EndPoints( end_points, A );
98 this->_Skeleton( end_points, A );
101 // -------------------------------------------------------------------------
102 template< class _TImage >
103 void fpa::Image::SkeletonFilter< _TImage >::
104 _EndPoints( std::vector< TIndex >& end_points, _TAdjacencies& A )
106 auto marks = this->GetMarks( );
107 auto mst = this->GetMinimumSpanningTree( );
108 auto spac = marks->GetSpacing( );
111 marks->SetLargestPossibleRegion( mst->GetLargestPossibleRegion( ) );
112 marks->SetRequestedRegion( mst->GetRequestedRegion( ) );
113 marks->SetBufferedRegion( mst->GetBufferedRegion( ) );
114 marks->SetSpacing( mst->GetSpacing( ) );
115 marks->SetOrigin( mst->GetOrigin( ) );
116 marks->SetDirection( mst->GetDirection( ) );
118 marks->FillBuffer( 0 );
120 // BFS from maximum queue
121 while( this->m_SkeletonQueue.size( ) > 0 )
124 auto nIt = this->m_SkeletonQueue.begin( );
126 this->m_SkeletonQueue.erase( nIt );
128 // Mark it and update end-points
129 unsigned char m = marks->GetPixel( n.second );
132 marks->SetPixel( n.second, 1 );
133 end_points.push_back( n.second );
136 TIndex it = n.second;
137 TIndex p = mst->GetParent( it );
140 this->_MarkSphere( it );
142 p = mst->GetParent( it );
145 this->_MarkSphere( it );
151 // -------------------------------------------------------------------------
152 template< class _TImage >
153 void fpa::Image::SkeletonFilter< _TImage >::
154 _Skeleton( const std::vector< TIndex >& end_points, _TAdjacencies& A )
156 typedef itk::Image< unsigned long, Self::Dimension > _TTagsImage;
157 typedef typename TMST::TPath _TPath;
159 auto mst = this->GetMinimumSpanningTree( );
160 auto skeleton = this->GetSkeleton( );
163 typename _TTagsImage::Pointer tags = _TTagsImage::New( );
164 tags->SetLargestPossibleRegion( mst->GetLargestPossibleRegion( ) );
165 tags->SetRequestedRegion( mst->GetRequestedRegion( ) );
166 tags->SetBufferedRegion( mst->GetBufferedRegion( ) );
168 tags->FillBuffer( 0 );
169 for( auto eIt = end_points.begin( ); eIt != end_points.end( ); ++eIt )
172 TIndex p = mst->GetParent( it );
175 tags->SetPixel( it, tags->GetPixel( it ) + 1 );
177 p = mst->GetParent( it );
180 tags->SetPixel( it, tags->GetPixel( it ) + 1 );
184 // Build paths (branches)
185 for( auto eIt = end_points.begin( ); eIt != end_points.end( ); ++eIt )
188 TIndex p = mst->GetParent( it );
190 typename _TPath::Pointer path = _TPath::New( );
191 path->SetReferenceImage( mst );
194 if( tags->GetPixel( sIdx ) != tags->GetPixel( it ) )
196 // Ok, a new branch has been added
197 path->AddVertex( it );
198 skeleton->AddBranch( path );
200 // Update a new starting index
201 path = _TPath::New( );
202 path->SetReferenceImage( mst );
206 path->AddVertex( it );
208 p = mst->GetParent( it );
212 // Finally, add last branch
213 path->AddVertex( it );
214 skeleton->AddBranch( path );
219 // -------------------------------------------------------------------------
220 template< class _TImage >
221 void fpa::Image::SkeletonFilter< _TImage >::
222 _MarkSphere( const TIndex& idx )
224 typedef itk::ImageRegionIteratorWithIndex< TMarks > _TMarksIt;
226 static const double _eps = std::sqrt( double( Self::Dimension + 1 ) );
227 auto input = this->GetInput( );
228 auto marks = this->GetMarks( );
229 auto spac = input->GetSpacing( );
230 auto region = input->GetRequestedRegion( );
232 typename _TImage::PointType cnt;
233 input->TransformIndexToPhysicalPoint( idx, cnt );
234 double r = double( input->GetPixel( idx ) ) * _eps;
237 for( unsigned int d = 0; d < Self::Dimension; ++d )
239 long off = long( std::ceil( r / double( spac[ d ] ) ) );
242 i0[ d ] = idx[ d ] - off;
243 i1[ d ] = idx[ d ] + off;
245 if( i0[ d ] < region.GetIndex( )[ d ] )
246 i0[ d ] = region.GetIndex( )[ d ];
248 if( i1[ d ] >= region.GetIndex( )[ d ] + region.GetSize( )[ d ] )
249 i1[ d ] = region.GetIndex( )[ d ] + region.GetSize( )[ d ] - 1;
253 typename _TImage::SizeType size;
254 for( unsigned int d = 0; d < Self::Dimension; ++d )
255 size[ d ] = i1[ d ] - i0[ d ] + 1;
257 typename _TImage::RegionType neighRegion;
258 neighRegion.SetIndex( i0 );
259 neighRegion.SetSize( size );
261 _TMarksIt mIt( marks, neighRegion );
262 for( mIt.GoToBegin( ); !mIt.IsAtEnd( ); ++mIt )
264 TIndex w = mIt.GetIndex( );
265 typename _TImage::PointType p;
266 marks->TransformIndexToPhysicalPoint( w, p );
272 #endif // __fpa__Image__SkeletonFilter__hxx__