diff --git a/Modules/AlgorithmsExt/mitkUnstructuredGridClusteringFilter.cpp b/Modules/AlgorithmsExt/mitkUnstructuredGridClusteringFilter.cpp
index 44f3044b73..cccc2b4b89 100644
--- a/Modules/AlgorithmsExt/mitkUnstructuredGridClusteringFilter.cpp
+++ b/Modules/AlgorithmsExt/mitkUnstructuredGridClusteringFilter.cpp
@@ -1,37 +1,107 @@
 /*===================================================================
 
 The Medical Imaging Interaction Toolkit (MITK)
 
 Copyright (c) German Cancer Research Center,
 Division of Medical and Biological Informatics.
 All rights reserved.
 
 This software is distributed WITHOUT ANY WARRANTY; without
 even the implied warranty of MERCHANTABILITY or FITNESS FOR
 A PARTICULAR PURPOSE.
 
 See LICENSE.txt or http://www.mitk.org for details.
 
 ===================================================================*/
 
 #include <mitkUnstructuredGridClusteringFilter.h>
 
 #include <vtkSmartPointer.h>
-#include <vtkPoints.h>
+#include <vtkPointLocator.h>
 #include <vtkUnstructuredGrid.h>
 
 
-mitk::UnstructuredGridClusteringFilter::UnstructuredGridClusteringFilter()
+mitk::UnstructuredGridClusteringFilter::UnstructuredGridClusteringFilter() : m_eps(0.0), m_MinPts(0)
 {
   this->m_UnstructGrid = mitk::UnstructuredGrid::New();
 }
 
 mitk::UnstructuredGridClusteringFilter::~UnstructuredGridClusteringFilter(){}
 
+std::map<int, bool> visited;
+std::map<int, bool> isNoise;
+std::map<int, bool> clusterMember;
+vtkSmartPointer<vtkPointLocator> pLocator;
+
 void mitk::UnstructuredGridClusteringFilter::GenerateOutputInformation()
 {
-  mitk::UnstructuredGrid::Pointer inputImage = const_cast<mitk::UnstructuredGrid*>(this->GetInput());
-  if(inputImage.IsNull()) return;
+  mitk::UnstructuredGrid::Pointer inputGrid = const_cast<mitk::UnstructuredGrid*>(this->GetInput());
+  if(inputGrid.IsNull()) return;
+
+  vtkSmartPointer<vtkUnstructuredGrid> vtkInpGrid = inputGrid->GetVtkUnstructuredGrid();
+  vtkSmartPointer<vtkPoints> inpPoints = vtkInpGrid->GetPoints();
+  pLocator =vtkSmartPointer<vtkPointLocator>::New();
+  std::vector<vtkPoints*> clusterVector;
+
+  pLocator->SetDataSet(vtkInpGrid);
+  pLocator->AutomaticOn();
+  pLocator->SetNumberOfPointsPerBucket(2);
+  pLocator->BuildLocator();
+
+  //fill the visited map with false for checking
+  for(int i=0; i<inpPoints->GetNumberOfPoints();i++)
+  {
+    visited[i] = false;
+    isNoise[i] = false;
+    clusterMember[i] = false;
+  }
+
+  for(int i=0; i<inpPoints->GetNumberOfPoints();i++)
+  {
+    visited[i] = true; //mark P as visited
+    vtkSmartPointer<vtkIdList> idList = vtkSmartPointer<vtkIdList>::New();
+    pLocator->FindPointsWithinRadius(m_eps, inpPoints->GetPoint(i), idList); //find neighbours
+    if(idList->GetNumberOfIds() < m_MinPts)
+    {
+      isNoise[i] = true;//point is noise - maybe just skip it?
+    }
+    else
+    {
+      vtkSmartPointer<vtkPoints> cluster = vtkSmartPointer<vtkPoints>::New();
+      clusterVector.push_back(cluster);
+      this->ExpandCluster(i,idList,cluster,inpPoints);
+    }
+  }
 
   m_UnstructGrid = this->GetOutput();
 }
+
+void mitk::UnstructuredGridClusteringFilter::ExpandCluster(int id, vtkIdList *pointIDs, vtkPoints* cluster, vtkPoints* inpPoints)
+{
+  cluster->InsertNextPoint(inpPoints->GetPoint(id)); //add Point to Cluster
+
+  vtkSmartPointer<vtkPoints> neighbours = vtkSmartPointer<vtkPoints>::New();
+  inpPoints->GetPoints(pointIDs,neighbours);
+
+  for(int i=0; i<pointIDs->GetNumberOfIds();i++)
+  {
+    if(!visited[pointIDs->GetId(i)]) //if P is not visited
+    {
+      visited[pointIDs->GetId(i)] = true; // mark P as visited
+      vtkSmartPointer<vtkIdList> idList = vtkSmartPointer<vtkIdList>::New();
+      pLocator->FindPointsWithinRadius(m_eps, inpPoints->GetPoint(pointIDs->GetId(i)), idList); //find neighbours
+      if(idList->GetNumberOfIds() >= m_MinPts)
+      {
+        for(int j=0; j<idList->GetNumberOfIds();j++)//join every point in range to the points
+        {
+          pointIDs->InsertNextId(idList->GetId(j));
+        }
+      }
+    }
+    if(!clusterMember[pointIDs->GetId(i)]) //P ist not yet member of any cluster
+    {
+      clusterMember[pointIDs->GetId(i)] = true;
+      cluster->InsertNextPoint(inpPoints->GetPoint(pointIDs->GetId(i)));
+    }
+  }
+}
diff --git a/Modules/AlgorithmsExt/mitkUnstructuredGridClusteringFilter.h b/Modules/AlgorithmsExt/mitkUnstructuredGridClusteringFilter.h
index 4123e47a22..942ed72f88 100644
--- a/Modules/AlgorithmsExt/mitkUnstructuredGridClusteringFilter.h
+++ b/Modules/AlgorithmsExt/mitkUnstructuredGridClusteringFilter.h
@@ -1,57 +1,99 @@
 /*===================================================================
 
 The Medical Imaging Interaction Toolkit (MITK)
 
 Copyright (c) German Cancer Research Center,
 Division of Medical and Biological Informatics.
 All rights reserved.
 
 This software is distributed WITHOUT ANY WARRANTY; without
 even the implied warranty of MERCHANTABILITY or FITNESS FOR
 A PARTICULAR PURPOSE.
 
 See LICENSE.txt or http://www.mitk.org for details.
 
 ===================================================================*/
 
 #ifndef _MITKUNSTRUCTUREDGRIDCLUSTERINGFILTER_h__
 #define _MITKUNSTRUCTUREDGRIDCLUSTERINGFILTER_h__
 
 #include <MitkAlgorithmsExtExports.h>
 
 #include <mitkCommon.h>
 
 #include <mitkUnstructuredGrid.h>
 #include <mitkUnstructuredGridToUnstructuredGridFilter.h>
+#include <vtkIdList.h>
+#include <vtkPoints.h>
 
 
 namespace mitk {
 
+   /**
+   * @brief The UnstructuredGridClusteringFilter class
+   *
+   * DBSCAN algorithm:
+   *
+   *     DBSCAN(D, eps, MinPts)
+   *     C = 0
+   *     for each unvisited point P in dataset D
+   *       mark P as visited
+   *       N = D.regionQuery(P, eps)
+   *       if sizeof(N) < MinPts
+   *         mark P as NOISE
+   *       else
+   *         C = next cluster
+   *         expandCluster(P, N, C, eps, MinPts)
+   *
+   *     expandCluster(P, N, C, eps, MinPts)
+   *       add P to cluster C
+   *       for each point P' in N
+   *         if P' is not visited
+   *           mark P' as visited
+   *           N' = D.regionQuery(P', eps)
+   *           if sizeof(N') >= MinPts
+   *             N = N joined with N'
+   *         if P' is not yet member of any cluster
+   *           add P' to cluster C
+   */
+
   class MitkAlgorithmsExt_EXPORT UnstructuredGridClusteringFilter
       : public UnstructuredGridToUnstructuredGridFilter
   {
     public:
 
       mitkClassMacro(UnstructuredGridClusteringFilter, UnstructuredGridToUnstructuredGridFilter)
       itkFactorylessNewMacro(Self)
       itkCloneMacro(Self)
 
+      itkSetMacro(eps, double)
+      itkGetMacro(eps, double)
+
+      itkSetMacro(MinPts, int)
+      itkGetMacro(MinPts, int)
+
       virtual void GenerateOutputInformation();
 
     protected:
 
       UnstructuredGridClusteringFilter();
 
       virtual ~UnstructuredGridClusteringFilter();
 
   private:
 
+      void ExpandCluster(int id, vtkIdList* pointIDs, vtkPoints* cluster, vtkPoints *inpPoints);
+
       mitk::UnstructuredGrid::Pointer m_UnstructGrid;
 
+      double m_eps;
+
+      int m_MinPts;
+
   };
 
 } // namespace mitk
 
 #endif //_MITKUNSTRUCTUREDGRIDCLUSTERINGFILTER_h__