diff --git a/Modules/DiffusionImaging/Quantification/IODataStructures/TbssImages/mitkNrrdTbssRoiImageWriter.cpp b/Modules/DiffusionImaging/Quantification/IODataStructures/TbssImages/mitkNrrdTbssRoiImageWriter.cpp
index 220c016eda..b5ead85460 100644
--- a/Modules/DiffusionImaging/Quantification/IODataStructures/TbssImages/mitkNrrdTbssRoiImageWriter.cpp
+++ b/Modules/DiffusionImaging/Quantification/IODataStructures/TbssImages/mitkNrrdTbssRoiImageWriter.cpp
@@ -1,147 +1,147 @@
 /*===================================================================
 
 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 __mitkNrrdTbssRoiImageWriter__cpp
 #define __mitkNrrdTbssRoiImageWriter__cpp
 
 #include "mitkNrrdTbssRoiImageWriter.h"
 #include "itkMetaDataDictionary.h"
 #include "itkMetaDataObject.h"
 #include "itkNrrdImageIO.h"
 //#include "itkNiftiImageIO.h"
 #include "itkImageFileWriter.h"
 #include "itksys/SystemTools.hxx"
 
 #include <iostream>
 #include <fstream>
 
 
 mitk::NrrdTbssRoiImageWriter::NrrdTbssRoiImageWriter()
   : m_FileName(""), m_FilePrefix(""), m_FilePattern(""), m_Success(false)
 {
   this->SetNumberOfRequiredInputs( 1 );
 }
 
 
 mitk::NrrdTbssRoiImageWriter::~NrrdTbssRoiImageWriter()
 {}
 
 void mitk::NrrdTbssRoiImageWriter::GenerateData()
 {
   m_Success = false;
   InputType* input = this->GetInput();
 
   if (input == nullptr)
   {
     itkWarningMacro(<<"Sorry, input to NrrdTbssImageWriter is NULL!")
     return;
   }
   if ( m_FileName == "" )
   {
     itkWarningMacro( << "Sorry, filename has not been set!" )
     return ;
   }
 
 
   char keybuffer[512];
-  char valbuffer[512];
+  std::stringstream valbuffer;
 
   std::vector< itk::Index<3> > roi = input->GetRoi();
 
   auto it = roi.begin();
 
   int i=0;
   while(it != roi.end())
   {
     itk::Index<3> ix = *it;
 
     sprintf( keybuffer, "ROI_index_%04d", i );
-    sprintf( valbuffer, "%ld %ld %ld", ix[0],ix[1],ix[2]);
+    valbuffer << ix[0] << " " << ix[1] << " " << ix[2];
 
-    std::cout << valbuffer << std::endl;
+    std::cout << valbuffer.str() << std::endl;
 
     //input->GetImage()->GetMetaDataDictionary();
 
-    itk::EncapsulateMetaData< std::string >(input->GetImage()->GetMetaDataDictionary(), std::string(keybuffer), std::string(valbuffer));
+    itk::EncapsulateMetaData< std::string >(input->GetImage()->GetMetaDataDictionary(), std::string(keybuffer), valbuffer.str());
 
     it++;
     ++i;
   }
 
   std::string structure = input->GetStructure();
   itk::EncapsulateMetaData< std::string >(input->GetImage()->GetMetaDataDictionary(), "structure", structure);
 
   typedef itk::Image<unsigned char,3> ImageType;
   ImageType::Pointer img = input->GetImage();
 
   itk::NrrdImageIO::Pointer io = itk::NrrdImageIO::New();
   io->SetFileType( itk::ImageIOBase::Binary );
   io->UseCompressionOn();
 
 
   typedef itk::ImageFileWriter<ImageType> WriterType;
   WriterType::Pointer nrrdWriter = WriterType::New();
   nrrdWriter->UseInputMetaDataDictionaryOn();
   nrrdWriter->SetInput( img );
   nrrdWriter->SetImageIO(io);
   nrrdWriter->SetFileName(m_FileName);
   // nrrdWriter->UseCompressionOn();
   nrrdWriter->SetImageIO(io);
   try
   {
     nrrdWriter->Update();
   }
   catch (itk::ExceptionObject e)
   {
     std::cout << e << std::endl;
   }
 
   m_Success = true;
 }
 
 
 void mitk::NrrdTbssRoiImageWriter::SetInput( InputType* tbssVol )
 {
   this->ProcessObject::SetNthInput( 0, tbssVol );
 }
 
 
 mitk::TbssRoiImage* mitk::NrrdTbssRoiImageWriter::GetInput()
 {
   if ( this->GetNumberOfInputs() < 1 )
   {
     return nullptr;
   }
   else
   {
     return dynamic_cast<InputType*> ( this->ProcessObject::GetInput( 0 ) );
   }
 }
 
 
 std::vector<std::string> mitk::NrrdTbssRoiImageWriter::GetPossibleFileExtensions()
 {
   std::vector<std::string> possibleFileExtensions;
   possibleFileExtensions.push_back(".roi");
   return possibleFileExtensions;
 }
 
 std::string mitk::NrrdTbssRoiImageWriter::GetSupportedBaseData() const
 {
   return TbssRoiImage::GetStaticNameOfClass();
 }
 
 #endif //__mitkNrrdTbssRoiImageWriter__cpp