void FinishVertex(VertexDescriptorType v, VertexDescriptorType sourceNode)
  {
    itk::Index<2> targetIndex = ITKHelpers::CreateIndex(v);
    itk::ImageRegion<2> targetRegion = ITKHelpers::GetRegionInRadiusAroundPixel(targetIndex, this->HalfWidth);

    itk::Index<2> sourceIndex = ITKHelpers::CreateIndex(sourceNode);
    itk::ImageRegion<2> sourceRegion = ITKHelpers::GetRegionInRadiusAroundPixel(sourceIndex, this->HalfWidth);

    emit signal_RefreshResult(sourceRegion, targetRegion);
    emit signal_RefreshImage();
  };
void BasicViewerWidget<TImage>::ConnectVisitor(TVisitor* visitor)
{
  // These are all BlockingQueuedConnection because the 'visitor' is not in the GUI thread.

  QObject::connect(visitor, SIGNAL(signal_RefreshImage()),
                   this, SLOT(slot_UpdateImage()),
                   Qt::BlockingQueuedConnection);

  QObject::connect(visitor, SIGNAL(signal_RefreshSource(const itk::ImageRegion<2>&,
                                                        const itk::ImageRegion<2>&)),
                   this, SLOT(slot_UpdateSource(const itk::ImageRegion<2>&,
                                                const itk::ImageRegion<2>&)),
                   Qt::BlockingQueuedConnection);

  QObject::connect(visitor, SIGNAL(signal_RefreshTarget(const itk::ImageRegion<2>&)),
                   this, SLOT(slot_UpdateTarget(const itk::ImageRegion<2>&)),
                   Qt::BlockingQueuedConnection);

}
// Run with: Data/trashcan.mha Data/trashcan_mask.mha 15 filled.mha
int main(int argc, char *argv[])
{
  // Verify arguments
  if(argc != 5)
    {
    std::cerr << "Required arguments: image.mha imageMask.mha patchHalfWidth output.mha" << std::endl;
    std::cerr << "Input arguments: ";
    for(int i = 1; i < argc; ++i)
      {
      std::cerr << argv[i] << " ";
      }
    return EXIT_FAILURE;
    }

  // Setup the GUI system
  QApplication app( argc, argv );

  // Parse arguments
  std::string imageFilename = argv[1];
  std::string maskFilename = argv[2];

  std::stringstream ssPatchRadius;
  ssPatchRadius << argv[3];
  unsigned int patchHalfWidth = 0;
  ssPatchRadius >> patchHalfWidth;

  std::string outputFilename = argv[4];

  // Output arguments
  std::cout << "Reading image: " << imageFilename << std::endl;
  std::cout << "Reading mask: " << maskFilename << std::endl;
  std::cout << "Patch half width: " << patchHalfWidth << std::endl;
  std::cout << "Output: " << outputFilename << std::endl;

  typedef FloatVectorImageType ImageType;

  typedef  itk::ImageFileReader<ImageType> ImageReaderType;
  ImageReaderType::Pointer imageReader = ImageReaderType::New();
  imageReader->SetFileName(imageFilename);
  imageReader->Update();

  ImageType* image = imageReader->GetOutput();
  itk::ImageRegion<2> fullRegion = imageReader->GetOutput()->GetLargestPossibleRegion();

  Mask::Pointer mask = Mask::New();
  mask->Read(maskFilename);

  std::cout << "hole pixels: " << mask->CountHolePixels() << std::endl;
  std::cout << "valid pixels: " << mask->CountValidPixels() << std::endl;

  std::cout << "image has " << image->GetNumberOfComponentsPerPixel() << " components." << std::endl;

  typedef ImagePatchPixelDescriptor<ImageType> ImagePatchPixelDescriptorType;

  // Create the graph
  typedef boost::grid_graph<2> VertexListGraphType;
  boost::array<std::size_t, 2> graphSideLengths = { { fullRegion.GetSize()[0],
                                                      fullRegion.GetSize()[1] } };
  VertexListGraphType graph(graphSideLengths);
  typedef boost::graph_traits<VertexListGraphType>::vertex_descriptor VertexDescriptorType;

  // Get the index map
  typedef boost::property_map<VertexListGraphType, boost::vertex_index_t>::const_type IndexMapType;
  IndexMapType indexMap(get(boost::vertex_index, graph));

  // Create the priority map
  typedef boost::vector_property_map<float, IndexMapType> PriorityMapType;
  PriorityMapType priorityMap(num_vertices(graph), indexMap);

  // Create the boundary status map. A node is on the current boundary if this property is true.
  // This property helps the boundaryNodeQueue because we can mark here if a node has become no longer
  // part of the boundary, so when the queue is popped we can check this property to see if it should
  // actually be processed.
  typedef boost::vector_property_map<bool, IndexMapType> BoundaryStatusMapType;
  BoundaryStatusMapType boundaryStatusMap(num_vertices(graph), indexMap);

  // Create the descriptor map. This is where the data for each pixel is stored.
  typedef boost::vector_property_map<ImagePatchPixelDescriptorType, IndexMapType> ImagePatchDescriptorMapType;
  ImagePatchDescriptorMapType imagePatchDescriptorMap(num_vertices(graph), indexMap);

  //ImagePatchDescriptorMapType smallImagePatchDescriptorMap(num_vertices(graph), indexMap);

  // Create the patch inpainter. The inpainter needs to know the status of each
  // pixel to determine if they should be inpainted.
  typedef MaskImagePatchInpainter InpainterType;
  MaskImagePatchInpainter patchInpainter(patchHalfWidth, mask);

  // Create the priority function
//   typedef PriorityRandom PriorityType;
//   PriorityType priorityFunction;
  typedef PriorityOnionPeel PriorityType;
  PriorityType priorityFunction(mask, patchHalfWidth);

  // Create the boundary node queue. The priority of each node is used to order the queue.
  typedef boost::vector_property_map<std::size_t, IndexMapType> IndexInHeapMap;
  IndexInHeapMap index_in_heap(indexMap);

  // Create the priority compare functor (we want the highest priority nodes to be first in the queue)
  typedef std::greater<float> PriorityCompareType;
  PriorityCompareType lessThanFunctor;

  typedef boost::d_ary_heap_indirect<VertexDescriptorType, 4, IndexInHeapMap, PriorityMapType, PriorityCompareType>
                                    BoundaryNodeQueueType;
  BoundaryNodeQueueType boundaryNodeQueue(priorityMap, index_in_heap, lessThanFunctor);

  // Create the descriptor visitor
  typedef ImagePatchDescriptorVisitor<VertexListGraphType, ImageType, ImagePatchDescriptorMapType>
          ImagePatchDescriptorVisitorType;
  ImagePatchDescriptorVisitorType imagePatchDescriptorVisitor(image, mask, imagePatchDescriptorMap, patchHalfWidth);
  //ImagePatchDescriptorVisitorType imagePatchDescriptorVisitor(cielabImage,
  //                                                            mask, imagePatchDescriptorMap, patchHalfWidth);

  typedef ImagePatchDifference<ImagePatchPixelDescriptorType, SumAbsolutePixelDifference<ImageType::PixelType> >
            ImagePatchDifferenceType;
  ImagePatchDifferenceType imagePatchDifferenceFunction;

//   typedef WeightedSumAbsolutePixelDifference<ImageType::PixelType> PixelDifferenceFunctorType;
//   PixelDifferenceFunctorType pixelDifferenceFunctor;
//   std::vector<float> weights;
//   weights.push_back(1.0f);
//   weights.push_back(1.0f);
//   weights.push_back(1.0f);
//   float gradientWeight = 500.0f;
//   weights.push_back(gradientWeight);
//   weights.push_back(gradientWeight);
//   pixelDifferenceFunctor.Weights = weights;
//   std::cout << "Weights: ";
//   OutputHelpers::OutputVector(pixelDifferenceFunctor.Weights);

//   typedef ImagePatchDifference<ImagePatchPixelDescriptorType, PixelDifferenceFunctorType >
//           ImagePatchDifferenceType;
// 
//   ImagePatchDifferenceType imagePatchDifferenceFunction(pixelDifferenceFunctor);

  typedef CompositeDescriptorVisitor<VertexListGraphType> CompositeDescriptorVisitorType;
  CompositeDescriptorVisitorType compositeDescriptorVisitor;
  compositeDescriptorVisitor.AddVisitor(&imagePatchDescriptorVisitor);

  typedef CompositeAcceptanceVisitor<VertexListGraphType> CompositeAcceptanceVisitorType;
  CompositeAcceptanceVisitorType compositeAcceptanceVisitor;

  typedef InpaintingVisitor<VertexListGraphType, ImageType, BoundaryNodeQueueType,
                            CompositeDescriptorVisitorType, CompositeAcceptanceVisitorType, PriorityType,
                            PriorityMapType, BoundaryStatusMapType>
                            InpaintingVisitorType;
  InpaintingVisitorType inpaintingVisitor(image, mask, boundaryNodeQueue,
                                          compositeDescriptorVisitor, compositeAcceptanceVisitor, priorityMap,
                                          &priorityFunction, patchHalfWidth,
                                          boundaryStatusMap, outputFilename);

  typedef DisplayVisitor<VertexListGraphType, ImageType> DisplayVisitorType;
  DisplayVisitorType displayVisitor(image, mask, patchHalfWidth);

  typedef DebugVisitor<VertexListGraphType, ImageType, BoundaryStatusMapType, BoundaryNodeQueueType>
          DebugVisitorType;
  DebugVisitorType debugVisitor(image, mask, patchHalfWidth, boundaryStatusMap, boundaryNodeQueue);

  LoggerVisitor<VertexListGraphType> loggerVisitor("log.txt");

  PaintPatchVisitor<VertexListGraphType, ImageType> inpaintRGBVisitor(image,
                                                                      mask.GetPointer(), patchHalfWidth);

  typedef CompositeInpaintingVisitor<VertexListGraphType> CompositeInpaintingVisitorType;
  CompositeInpaintingVisitorType compositeInpaintingVisitor;
  compositeInpaintingVisitor.AddVisitor(&inpaintingVisitor);
  //compositeInpaintingVisitor.AddVisitor(&inpaintRGBVisitor);
  compositeInpaintingVisitor.AddVisitor(&displayVisitor);
  compositeInpaintingVisitor.AddVisitor(&debugVisitor);
  //compositeInpaintingVisitor.AddVisitor(&loggerVisitor);

  InitializePriority(mask, boundaryNodeQueue, priorityMap, &priorityFunction, boundaryStatusMap);

  // Initialize the boundary node queue from the user provided mask image.
  InitializeFromMaskImage<CompositeInpaintingVisitorType, VertexDescriptorType>(mask, &compositeInpaintingVisitor);

  // Create the nearest neighbor finders
  typedef LinearSearchKNNProperty<ImagePatchDescriptorMapType,
                                  ImagePatchDifferenceType > KNNSearchType;
  KNNSearchType knnSearch(imagePatchDescriptorMap, 50000, 1, imagePatchDifferenceFunction);

  // For debugging we use LinearSearchBestProperty instead of DefaultSearchBest
  // because it can output the difference value.
  typedef LinearSearchBestProperty<ImagePatchDescriptorMapType,
                                   ImagePatchDifferenceType > BestSearchType;
  BestSearchType bestSearch(imagePatchDescriptorMap, imagePatchDifferenceFunction);

  BasicViewerWidget<ImageType> basicViewerWidget(image, mask);
  basicViewerWidget.show();
  
  // These connections are Qt::BlockingQueuedConnection because the algorithm quickly
  // goes on to fill the hole, and since we are sharing the image memory, we want to make sure these things are
  // refreshed at the right time, not after the hole has already been filled
  // (this actually happens, it is not just a theoretical thing).
  QObject::connect(&displayVisitor, SIGNAL(signal_RefreshImage()), &basicViewerWidget, SLOT(slot_UpdateImage()),
                   Qt::BlockingQueuedConnection);
  QObject::connect(&displayVisitor, SIGNAL(signal_RefreshSource(const itk::ImageRegion<2>&,
                                                                const itk::ImageRegion<2>&)),
                   &basicViewerWidget, SLOT(slot_UpdateSource(const itk::ImageRegion<2>&,
                                                              const itk::ImageRegion<2>&)),
                   Qt::BlockingQueuedConnection);
  QObject::connect(&displayVisitor, SIGNAL(signal_RefreshTarget(const itk::ImageRegion<2>&)),
                   &basicViewerWidget, SLOT(slot_UpdateTarget(const itk::ImageRegion<2>&)),
                   Qt::BlockingQueuedConnection);
  QObject::connect(&displayVisitor, SIGNAL(signal_RefreshResult(const itk::ImageRegion<2>&,
                                                                const itk::ImageRegion<2>&)),
                   &basicViewerWidget, SLOT(slot_UpdateResult(const itk::ImageRegion<2>&,
                                                              const itk::ImageRegion<2>&)),
                   Qt::BlockingQueuedConnection);

//   TopPatchesDialog<ImageType> topPatchesDialog(image, mask, patchHalfWidth, &basicViewerWidget);
//   typedef VisualSelectionBest<ImageType> ManualSearchType;
//   ManualSearchType manualSearchBest(image, mask, patchHalfWidth, &topPatchesDialog);

  typedef DefaultSearchBest ManualSearchType;
  DefaultSearchBest manualSearchBest;
  
  // By specifying the radius as the image size/8, we are searching up to 1/4 of the image each time
  typedef NeighborhoodSearch<VertexDescriptorType> NeighborhoodSearchType;
  NeighborhoodSearchType neighborhoodSearch(fullRegion, fullRegion.GetSize()[0]/8);

  // Run the remaining inpainting
  QtConcurrent::run(boost::bind(InpaintingAlgorithmWithLocalSearch<
                                VertexListGraphType, CompositeInpaintingVisitorType, BoundaryStatusMapType,
                                BoundaryNodeQueueType, NeighborhoodSearchType, KNNSearchType, BestSearchType,
                                ManualSearchType, InpainterType>,
                                graph, compositeInpaintingVisitor, &boundaryStatusMap, &boundaryNodeQueue,
                                neighborhoodSearch, knnSearch, bestSearch, boost::ref(manualSearchBest),
                                patchInpainter));

  return app.exec();
}
 void DiscoverVertex(VertexDescriptorType v) const
 {
   // std::cout << "DisplayVisitor::DiscoverVertex" << std::endl;
   emit signal_RefreshImage();
 };