diff --git a/Core/Code/IO/mitkDicomSeriesReader.h b/Core/Code/IO/mitkDicomSeriesReader.h index a66a11b749..81df6c582a 100644 --- a/Core/Code/IO/mitkDicomSeriesReader.h +++ b/Core/Code/IO/mitkDicomSeriesReader.h @@ -1,445 +1,445 @@ /*========================================================================= Program: Medical Imaging & Interaction Toolkit Language: C++ Date: $Date$ Version: $Revision$ Copyright (c) German Cancer Research Center, Division of Medical and Biological Informatics. All rights reserved. See MITKCopyright.txt or http://www.mitk.org/copyright.html for details. This software is distributed WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the above copyright notices for more information. =========================================================================*/ #ifndef mitkDicomSeriesReader_h #define mitkDicomSeriesReader_h #include "mitkDataNode.h" #include "mitkConfig.h" #include #include #include #include #include #include #include #include #include #include namespace mitk { /** \brief Loading DICOM images as MITK images. - \ref DicomSeriesReader_purpose - \ref DicomSeriesReader_limitations - \ref DicomSeriesReader_usage - \ref DicomSeriesReader_sorting - \ref DicomSeriesReader_sorting1 - \ref DicomSeriesReader_sorting2 - \ref DicomSeriesReader_sorting3 - \ref DicomSeriesReader_sorting4 - \ref DicomSeriesReader_tests \section DicomSeriesReader_purpose Purpose DicomSeriesReader serves as a central class for loading DICOM images as mitk::Image. As the term "DICOM image" covers a huge variety of possible modalities and implementations, and since MITK assumes that 3D images are made up of continuous blocks of slices without any gaps or changes in orientation, the loading mechanism must implement a number of decisions and compromises. The main intention of this implementation is not efficiency but correcness of generated slice positions! \section DicomSeriesReader_limitations Assumptions and limitations The class is working only with GDCM 2.0.14 (or possibly newer). This version is the default of an MITK super-build. Support for other versions or ITK's DicomIO was dropped because of the associated complexity of DicomSeriesReader. \b Assumptions - expected to work for SOP Classes CT Image Storage and MR Image Storage (NOT for the "Enhanced" variants containing multi-frame images) - special treatment for a certain type of Philips 3D ultrasound (recogized by tag 3001,0010 set to "Philips3D") - loader will always attempt to read multiple single slices as a single 3D image volume (i.e. mitk::Image) - slices will be grouped by basic properties such as orientation, rows, columns, spacing and grouped into as large blocks as possible \b Options - images that cover the same piece of space (i.e. position, orientation, and dimensions are equal) can be interpreted as time-steps of the same image, i.e. a series will be loaded as 3D+t \b Limitations - the 3D+t assumption only works if all time-steps have an equal number of slices and if all have the Acquisition Time attribute set to meaningful values - Images from tilted CT gantries CAN ONLY be loaded as a series of single-slice images, since mitk::Image or the accompanying mapper are not (yet?) capable of representing such geometries - Secondary Capture images are expected to have the (0018,2010) tag describing the pixel spacing. If only the (0028,0030) tag is set, the spacing will be misinterpreted as (1,1) \section DicomSeriesReader_usage Usage The starting point for an application is a set of DICOM files that should be loaded. For convenience, DicomSeriesReader can also parse a whole directory for DICOM files, but an application should better know exactly what to load. Loading is then done in two steps: 1. Group the files into spatial blocks by calling GetSeries(). This method will sort all passed files into meaningful blocks that could fit into an mitk::Image. Sorting for 3D+t loading is optional but default. The \b return value of this function is a list of identifiers similar to DICOM UIDs, each associated to a sorted list of file names. 2. Load a sorted set of files by calling LoadDicomSeries(). This method expects go receive the sorting output of GetSeries(). The method will then invoke ITK methods to actually load the files into memory and put them into mitk::Images. Again, loading as 3D+t is optional. Example: \code // only a directory is known at this point: /home/who/dicom DicomSeriesReader::UidFileNamesMap allImageBlocks = DicomSeriesReader::GetSeries("/home/who/dicom/"); // file now divided into groups of identical image size, orientation, spacing, etc. // each of these lists should be loadable as an mitk::Image. DicomSeriesReader::StringContainer seriesToLoad = allImageBlocks[...]; // decide what to load // final step: load into DataNode (can result in 3D+t image) DataNode::Pointer node = DicomSeriesReader::LoadDicomSeries( oneBlockSorted ); Image::Pointer image = dynamic_cast( node->GetData() ); \endcode \section DicomSeriesReader_sorting Logic for sorting 2D slices from DICOM images into 3D+t blocks for mitk::Image The general sorting mechanism (implemented in GetSeries) groups and sorts a set of DICOM files, each assumed to contain a single CT/MR slice. In the following we refer to those file groups as "blocks", since this is what they are meant to become when loaded into an mitk::Image. \subsection DicomSeriesReader_sorting1 Step 1: Avoiding pure non-sense A first pass separates slices that cannot possibly be loaded together because of restrictions of mitk::Image. After this steps, each block contains only slices that match in all of the following DICOM tags: - (0020,0037) Image Orientation - (0028,0030) Pixel Spacing - (0018,0050) Slice Thickness - (0028,0010) Number Of Rows - (0028,0011) Number Of Columns - (0020,000e) Series Instance UID : could be argued about, might be dropped in the future (optionally) \subsection DicomSeriesReader_sorting2 Step 2: Sort slices spatially Before slices are further analyzed, they are sorted spatially. As implemented by GdcmSortFunction(), slices are sorted by 1. distance from origin (calculated using (0020,0032) Image Position Patient and (0020,0037) Image Orientation) 2. when distance is equal, (0008,0032) Acquisition Time is used as a backup criterion (necessary for meaningful 3D+t sorting) \subsection DicomSeriesReader_sorting3 Step 3: Ensure equal z spacing Since inter-slice distance is not recorded in DICOM tags, we must ensure that blocks are made up of slices that have equal distances between neighboring slices. This is especially necessary because itk::ImageSeriesReader is later used for the actual loading, and this class expects (and does nocht verify) equal inter-slice distance. To achieve such grouping, the inter-slice distance is calculated from the first two different slice positions of a block. Following slices are added to a block as long as they can be added by adding the calculated inter-slice distance to the last slice of the block. Slices that do not fit into the expected distance pattern, are set aside for further analysis. This grouping is done until each file has been assigned to a group. Slices that share a position in space are also sorted into separate blocks during this step. So the result of this step is a set of blocks that contain only slices with equal z spacing and uniqe slices at each position. \subsection DicomSeriesReader_sorting4 Step 4 (optional): group 3D blocks as 3D+t when possible This last step depends on an option of GetSeries(). When requested, image blocks from the previous step are merged again whenever two blocks occupy the same portion of space (i.e. same origin, number of slices and z-spacing). \section DicomSeriesReader_tests Tests regarding DICOM loading A number of tests have been implemented to check our assumptions regarding DICOM loading. Please see \ref DICOMTesting */ class MITK_CORE_EXPORT DicomSeriesReader { public: /** \brief Lists of filenames. */ typedef std::vector StringContainer; /** \brief For grouped lists of filenames, assigned an ID each. */ typedef std::map UidFileNamesMap; /** \brief Interface for the progress callback. */ typedef void (*UpdateCallBackMethod)(float); /** \brief Provide combination of preprocessor defines that was active during compilation. Since this class is a combination of several possible implementations, separated only by ifdef's, calling instances might want to know which flags were active at compile time. */ static std::string GetConfigurationString(); /** \brief Checks if a specific file contains DICOM data. */ static bool IsDicom(const std::string &filename); /** \brief see other GetSeries(). Find all series (and sub-series -- see details) in a particular directory. */ static UidFileNamesMap GetSeries(const std::string &dir, const StringContainer &restrictions = StringContainer()); /** \brief see other GetSeries(). \warning Untested, could or could not work. This differs only by having an additional restriction to a single known DICOM series. Internally, it uses the other GetSeries() method. */ static StringContainer GetSeries(const std::string &dir, const std::string &series_uid, const StringContainer &restrictions = StringContainer()); /** \brief PREFERRED version of this method - scan and sort DICOM files. Parse a list of files for images of DICOM series. For each series, an enumeration of the files contained in it is created. \return The resulting maps UID-like keys (based on Series Instance UID and slice properties) to sorted lists of file names. SeriesInstanceUID will be enhanced to be unique for each set of file names that is later loadable as a single mitk::Image. This implies that Image orientation, slice thickness, pixel spacing, rows, and columns must be the same for each file (i.e. the image slice contained in the file). If this separation logic requires that a SeriesInstanceUID must be made more specialized, it will follow the same logic as itk::GDCMSeriesFileNames to enhance the UID with more digits and dots. Optionally, more tags can be used to separate files into different logical series by setting the restrictions parameter. \warning Adding restrictions is not yet implemented! */ static UidFileNamesMap GetSeries(const StringContainer& files, bool sortTo3DPlust, const StringContainer &restrictions = StringContainer()); /** \brief See other GetSeries(). Use GetSeries(const StringContainer& files, bool sortTo3DPlust, const StringContainer &restrictions) instead. */ static UidFileNamesMap GetSeries(const StringContainer& files, const StringContainer &restrictions = StringContainer()); /** Loads a DICOM series composed by the file names enumerated in the file names container. If a callback method is supplied, it will be called after every progress update with a progress value in [0,1]. \param filenames The filenames to load. \param sort Whether files should be sorted spatially (true) or not (false - maybe useful if presorted) \param load4D Whether to load the files as 3D+t (if possible) */ static DataNode::Pointer LoadDicomSeries(const StringContainer &filenames, bool sort = true, bool load4D = true, UpdateCallBackMethod callback = 0); /** \brief See LoadDicomSeries! Just a slightly different interface. */ static bool LoadDicomSeries(const StringContainer &filenames, DataNode &node, bool sort = true, bool load4D = true, UpdateCallBackMethod callback = 0); protected: /** \brief for internal sorting. */ typedef std::pair TwoStringContainers; /** \brief Ensure an equal z-spacing for a group of files. Internally used by GetSeries. Returns two lists: the first one contins slices of equal inter-slice spacing. The second list contains remaining files, which need to be run through AnalyzeFileForITKImageSeriesReaderSpacingAssumption again. Relevant code that is matched here is in itkImageSeriesReader.txx (ImageSeriesReader::GenerateOutputInformation(void)), lines 176 to 245 (as of ITK 3.20) */ static TwoStringContainers AnalyzeFileForITKImageSeriesReaderSpacingAssumption(const StringContainer& files, const gdcm::Scanner::MappingType& tagValueMappings_); /** \brief Sort a set of file names in an order that is meaningful for loading them into an mitk::Image. \warning This method assumes that input files are similar in basic properties such as slice thicknes, image orientation, pixel spacing, rows, columns. It should always be ok to put the result of a call to GetSeries(..) into this method. Sorting order is determined by 1. image position along its normal (distance from world origin) 2. acquisition time If P denotes a position and T denotes a time step, this method will order slices from three timesteps like this: \verbatim P1T1 P1T2 P1T3 P2T1 P2T2 P2T3 P3T1 P3T2 P3T3 \endverbatim */ static StringContainer SortSeriesSlices(const StringContainer &unsortedFilenames); public: /** \brief Checks if a specific file is a Philips3D ultrasound DICOM file. */ static bool IsPhilips3DDicom(const std::string &filename); protected: /** \brief Read a Philips3D ultrasound DICOM file and put into an mitk::Image. */ static bool ReadPhilips3DDicom(const std::string &filename, mitk::Image::Pointer output_image); /** \brief Construct a UID that takes into account sorting criteria from GetSeries(). */ static std::string CreateMoreUniqueSeriesIdentifier( gdcm::Scanner::TagToValue& tagValueMap ); /** \brief Helper for CreateMoreUniqueSeriesIdentifier */ static std::string CreateSeriesIdentifierPart( gdcm::Scanner::TagToValue& tagValueMap, const gdcm::Tag& tag ); /** \brief Helper for CreateMoreUniqueSeriesIdentifier */ static std::string IDifyTagValue(const std::string& value); typedef itk::GDCMImageIO DcmIoType; /** \brief Progress callback for DicomSeriesReader. */ class CallbackCommand : public itk::Command { public: CallbackCommand(UpdateCallBackMethod callback) : m_Callback(callback) { } void Execute(const itk::Object *caller, const itk::EventObject&) { (*this->m_Callback)(static_cast(caller)->GetProgress()); } void Execute(itk::Object *caller, const itk::EventObject&) { (*this->m_Callback)(static_cast(caller)->GetProgress()); } protected: UpdateCallBackMethod m_Callback; }; /** \brief Scan for slice image information */ - static gdcm::Scanner ScanForSliceInformation( const StringContainer &filenames ); + static void ScanForSliceInformation( const StringContainer &filenames, gdcm::Scanner& scanner ); /** \brief Performs actual loading of a series and creates an image having the specified pixel type. */ template static void LoadDicom(const StringContainer &filenames, DataNode &node, bool sort, bool check_4d, UpdateCallBackMethod callback); /** \brief Feed files into itk::ImageSeriesReader and retrieve a 3D MITK image. \param command can be used for progress reporting */ template static Image::Pointer LoadDICOMByITK( const StringContainer&, CallbackCommand* command = NULL); /** \brief Sort files into time step blocks of a 3D+t image. Called by LoadDicom. Expects to be fed a single list of filenames that have been sorted by GetSeries previously (one map entry). This method will check how many timestep can be filled with given files. Assumption is that the number of time steps is determined by how often the first position in space repeats. I.e. if the first three files in the input parameter all describe the same location in space, we'll construct three lists of files. and sort the remaining files into them. \todo We can probably remove this method if we somehow transfer 3D+t information from GetSeries to LoadDicomSeries. */ static std::list SortIntoBlocksFor3DplusT( const StringContainer& presortedFilenames, const gdcm::Scanner::MappingType& tagValueMappings_, bool sort, bool& canLoadAs4D); /** \brief Defines spatial sorting for sorting by GDCM 2. Sorts by image position along image normal (distance from world origin). In cases of conflict, acquisition time is used as a secondary sort criterium. */ static bool GdcmSortFunction(const gdcm::DataSet &ds1, const gdcm::DataSet &ds2); /** \brief Copy information about files and DICOM tags from ITK's MetaDataDictionary and from the list of input files to the PropertyList of mitk::Image. \todo Tag copy must follow; image level will cause some additional files parsing, probably. */ static void CopyMetaDataToImageProperties( StringContainer filenames, const gdcm::Scanner::MappingType& tagValueMappings_, DcmIoType* io, Image* image); static void CopyMetaDataToImageProperties( std::list imageBlock, const gdcm::Scanner::MappingType& tagValueMappings_, DcmIoType* io, Image* image); }; } #endif /* MITKDICOMSERIESREADER_H_ */ diff --git a/Core/Code/IO/mitkDicomSeriesReader.txx b/Core/Code/IO/mitkDicomSeriesReader.txx index 8cb7410073..0835a60bcf 100644 --- a/Core/Code/IO/mitkDicomSeriesReader.txx +++ b/Core/Code/IO/mitkDicomSeriesReader.txx @@ -1,298 +1,307 @@ /*========================================================================= Program: Medical Imaging & Interaction Toolkit Language: C++ Date: $Date$ Version: $Revision$ Copyright (c) German Cancer Research Center, Division of Medical and Biological Informatics. All rights reserved. See MITKCopyright.txt or http://www.mitk.org/copyright.html for details. This software is distributed WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the above copyright notices for more information. =========================================================================*/ #ifndef MITKDICOMSERIESREADER_TXX_ #define MITKDICOMSERIESREADER_TXX_ #include #include #include namespace mitk { template void DicomSeriesReader::LoadDicom(const StringContainer &filenames, DataNode &node, bool sort, bool load4D, UpdateCallBackMethod callback) { const char* previousCLocale = setlocale(LC_NUMERIC, NULL); setlocale(LC_NUMERIC, "C"); std::locale previousCppLocale( std::cin.getloc() ); std::locale l( "C" ); std::cin.imbue(l); try { mitk::Image::Pointer image = mitk::Image::New(); CallbackCommand *command = callback ? new CallbackCommand(callback) : 0; /* special case for Philips 3D+t ultrasound images */ if ( DicomSeriesReader::IsPhilips3DDicom(filenames.front().c_str()) ) { ReadPhilips3DDicom(filenames.front().c_str(), image); } else { /* default case: assume "normal" image blocks, possibly 3D+t */ bool canLoadAs4D(true); - std::list imageBlocks = SortIntoBlocksFor3DplusT( filenames, ScanForSliceInformation(filenames).GetMappings(), sort, canLoadAs4D ); + gdcm::Scanner scanner; + ScanForSliceInformation(filenames, scanner); + + std::list imageBlocks = SortIntoBlocksFor3DplusT( filenames, scanner.GetMappings(), sort, canLoadAs4D ); unsigned int volume_count = imageBlocks.size(); if (volume_count == 1 || !canLoadAs4D || !load4D) { image = LoadDICOMByITK( imageBlocks.front() , command ); // load first 3D block } else { // It is 3D+t! Read it and store into mitk image typedef itk::Image ImageType; typedef itk::ImageSeriesReader ReaderType; DcmIoType::Pointer io = DcmIoType::New(); typename ReaderType::Pointer reader = ReaderType::New(); reader->SetImageIO(io); reader->ReverseOrderOff(); if (command) { reader->AddObserver(itk::ProgressEvent(), command); } unsigned int act_volume = 1u; reader->SetFileNames(imageBlocks.front()); reader->Update(); image->InitializeByItk(reader->GetOutput(), 1, volume_count); image->SetImportVolume(reader->GetOutput()->GetBufferPointer(), 0u); - DicomSeriesReader::CopyMetaDataToImageProperties( imageBlocks, ScanForSliceInformation(filenames).GetMappings(), io, image); + gdcm::Scanner scanner; + ScanForSliceInformation(filenames, scanner); + + DicomSeriesReader::CopyMetaDataToImageProperties( imageBlocks, scanner.GetMappings(), io, image); MITK_DEBUG << "Volume dimension: [" << image->GetDimension(0) << ", " << image->GetDimension(1) << ", " << image->GetDimension(2) << ", " << image->GetDimension(3) << "]"; #if (GDCM_MAJOR_VERSION == 2) && (GDCM_MINOR_VERSION < 1) && (GDCM_BUILD_VERSION < 15) // workaround for a GDCM 2 bug until version 2.0.15: // GDCM read spacing vector wrongly. Instead of "row spacing, column spacing", it misinterprets the DICOM tag as "column spacing, row spacing". // this is undone here, until we use a GDCM that has this issue fixed. // From the commit comments, GDCM 2.0.15 fixed the spacing interpretation with bug 2901181 // http://sourceforge.net/tracker/index.php?func=detail&aid=2901181&group_id=137895&atid=739587 Vector3D correctedImageSpacing = image->GetGeometry()->GetSpacing(); std::swap( correctedImageSpacing[0], correctedImageSpacing[1] ); image->GetGeometry()->SetSpacing( correctedImageSpacing ); #endif MITK_DEBUG << "Volume spacing: [" << image->GetGeometry()->GetSpacing()[0] << ", " << image->GetGeometry()->GetSpacing()[1] << ", " << image->GetGeometry()->GetSpacing()[2] << "]"; for (std::list::iterator df_it = ++imageBlocks.begin(); df_it != imageBlocks.end(); ++df_it) { reader->SetFileNames(*df_it); reader->Update(); image->SetImportVolume(reader->GetOutput()->GetBufferPointer(), act_volume++); } } } node.SetData( image ); setlocale(LC_NUMERIC, previousCLocale); std::cin.imbue(previousCppLocale); } catch (std::exception& e) { // reset locale then throw up setlocale(LC_NUMERIC, previousCLocale); std::cin.imbue(previousCppLocale); throw e; } } template Image::Pointer DicomSeriesReader::LoadDICOMByITK( const StringContainer& filenames, CallbackCommand* command ) { /******** Normal Case, 3D (also for GDCM < 2 usable) ***************/ mitk::Image::Pointer image = mitk::Image::New(); typedef itk::Image ImageType; typedef itk::ImageSeriesReader ReaderType; DcmIoType::Pointer io = DcmIoType::New(); typename ReaderType::Pointer reader = ReaderType::New(); reader->SetImageIO(io); reader->ReverseOrderOff(); if (command) { reader->AddObserver(itk::ProgressEvent(), command); } reader->SetFileNames(filenames); reader->Update(); image->InitializeByItk(reader->GetOutput()); image->SetImportVolume(reader->GetOutput()->GetBufferPointer()); - DicomSeriesReader::CopyMetaDataToImageProperties( filenames, ScanForSliceInformation(filenames).GetMappings(), io, image); + gdcm::Scanner scanner; + ScanForSliceInformation(filenames, scanner); + + DicomSeriesReader::CopyMetaDataToImageProperties( filenames, scanner.GetMappings(), io, image); MITK_DEBUG << "Volume dimension: [" << image->GetDimension(0) << ", " << image->GetDimension(1) << ", " << image->GetDimension(2) << "]"; #if (GDCM_MAJOR_VERSION == 2) && (GDCM_MINOR_VERSION < 1) && (GDCM_BUILD_VERSION < 15) // workaround for a GDCM 2 bug until version 2.0.15: // GDCM read spacing vector wrongly. Instead of "row spacing, column spacing", it misinterprets the DICOM tag as "column spacing, row spacing". // this is undone here, until we use a GDCM that has this issue fixed. // From the commit comments, GDCM 2.0.15 fixed the spacing interpretation with bug 2901181 // http://sourceforge.net/tracker/index.php?func=detail&aid=2901181&group_id=137895&atid=739587 Vector3D correctedImageSpacing = image->GetGeometry()->GetSpacing(); std::swap( correctedImageSpacing[0], correctedImageSpacing[1] ); image->GetGeometry()->SetSpacing( correctedImageSpacing ); #endif MITK_DEBUG << "Volume spacing: [" << image->GetGeometry()->GetSpacing()[0] << ", " << image->GetGeometry()->GetSpacing()[1] << ", " << image->GetGeometry()->GetSpacing()[2] << "]"; return image; } -gdcm::Scanner -DicomSeriesReader::ScanForSliceInformation(const StringContainer &filenames) +void +DicomSeriesReader::ScanForSliceInformation(const StringContainer &filenames, gdcm::Scanner& scanner) { - gdcm::Scanner scanner; - const gdcm::Tag ippTag(0x0020,0x0032); //Image position (Patient) scanner.AddTag(ippTag); // TODO what if tags don't exist? const gdcm::Tag tagSliceLocation(0x0020, 0x1041); // slice location scanner.AddTag( tagSliceLocation ); const gdcm::Tag tagInstanceNumber(0x0020, 0x0013); // (image) instance number scanner.AddTag( tagInstanceNumber ); const gdcm::Tag tagSOPInstanceNumber(0x0008, 0x0018); // SOP instance number scanner.AddTag( tagSOPInstanceNumber ); scanner.Scan(filenames); // make available image position for each file - - return scanner; - } std::list DicomSeriesReader::SortIntoBlocksFor3DplusT( const StringContainer& presortedFilenames, - const gdcm::Scanner::MappingType& tagValueMappings_, + const gdcm::Scanner::MappingType& tagValueMappings, bool sort, bool& canLoadAs4D ) { std::list imageBlocks; // ignore sort request, because most likely re-sorting is now needed due to changes in GetSeries(bug #8022) StringContainer sorted_filenames = DicomSeriesReader::SortSeriesSlices(presortedFilenames); - - gdcm::Scanner::MappingType& tagValueMappings = const_cast(tagValueMappings_); - + std::string firstPosition; unsigned int numberOfBlocks(0); // number of 3D image blocks const gdcm::Tag ippTag(0x0020,0x0032); //Image position (Patient) // loop files to determine number of image blocks for (StringContainer::const_iterator fileIter = sorted_filenames.begin(); fileIter != sorted_filenames.end(); ++fileIter) { - std::string position = tagValueMappings[fileIter->c_str()][ippTag]; + gdcm::Scanner::TagToValue tagToValueMap = tagValueMappings.find( fileIter->c_str() )->second; + + if(tagToValueMap.find(ippTag) == tagToValueMap.end()) + { + continue; + } + + std::string position = tagToValueMap.find(ippTag)->second; MITK_DEBUG << " " << *fileIter << " at " << position; if (firstPosition.empty()) { firstPosition = position; } if ( position == firstPosition ) { ++numberOfBlocks; } else { break; // enough information to know the number of image blocks } } MITK_DEBUG << " ==> Assuming " << numberOfBlocks << " time steps"; if (numberOfBlocks == 0) return imageBlocks; // only possible if called with no files // loop files to sort them into image blocks unsigned int numberOfExpectedSlices(0); for (unsigned int block = 0; block < numberOfBlocks; ++block) { StringContainer filesOfCurrentBlock; for ( StringContainer::const_iterator fileIter = sorted_filenames.begin() + block; fileIter != sorted_filenames.end(); //fileIter += numberOfBlocks) // TODO shouldn't this work? give invalid iterators on first attempts ) { filesOfCurrentBlock.push_back( *fileIter ); for (unsigned int b = 0; b < numberOfBlocks; ++b) { if (fileIter != sorted_filenames.end()) ++fileIter; } } imageBlocks.push_back(filesOfCurrentBlock); if (block == 0) { numberOfExpectedSlices = filesOfCurrentBlock.size(); } else { if (filesOfCurrentBlock.size() != numberOfExpectedSlices) { MITK_WARN << "DicomSeriesReader expected " << numberOfBlocks << " image blocks of " << numberOfExpectedSlices << " images each. Block " << block << " got " << filesOfCurrentBlock.size() << " instead. Cannot load this as 3D+t"; // TODO implement recovery (load as many slices 3D+t as much as possible) canLoadAs4D = false; } } } return imageBlocks; } } #endif