oDynamicDataManager.cc

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/*
  Implementation of class oDynamicDataManager

  - separators: X
  - doxygen: X
  - default initialization: X
  - CASTOR_DEBUG: none
  - CASTOR_VERBOSE: X
*/


#include "oDynamicDataManager.hh"
#include "oImageDimensionsAndQuantification.hh"

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/*
  Constructor oDynamicDataManager
*/
oDynamicDataManager::oDynamicDataManager()
{
  mp_ID = NULL;
  m_verbose = -1;
  m_nbTimeFrames = 1;
  mp_currentFrameIndex = NULL;
  m_respGatingFlag = false;
  m_rMotionCorrFlag = false;
  m_nbRespGates = 1;
  m2p_nbEventsPerRespGate = NULL;
  m2p_indexLastEventRespGate = NULL;
  mp_currentRespGateIndex = NULL;
  m_cardGatingFlag = false;
  m_cMotionCorrFlag = false;
  m_nbCardGates = 1;
  m2p_nbEventsPerCardGate = NULL;
  m2p_indexLastEventCardGate = NULL;
  mp_currentCardGateIndex = NULL;
  m_pMotionCorrFlag = false;
  m_nbPMotionTriggers = 0;
  mp_listPMotionTriggers = NULL;
  mp_currentPMotionIndex = NULL;
}

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/*
  Destructor oDynamicDataManager
*/
oDynamicDataManager::~oDynamicDataManager()
{
  for (int fr=0; fr<m_nbTimeFrames; fr++)
  {
    if (m2p_nbEventsPerRespGate && m2p_nbEventsPerRespGate[fr]) 
      delete m2p_nbEventsPerRespGate[fr];
    if (m2p_nbEventsPerCardGate && m2p_nbEventsPerCardGate[fr]) 
      delete m2p_nbEventsPerCardGate[fr];
    if (m2p_indexLastEventRespGate && m2p_indexLastEventRespGate[fr]) 
      delete m2p_indexLastEventRespGate[fr];
    if (m2p_indexLastEventCardGate && m2p_indexLastEventCardGate[fr]) 
      delete m2p_indexLastEventCardGate[fr];
  }

  if (m2p_nbEventsPerRespGate!=NULL) delete m2p_nbEventsPerRespGate;
  if (m2p_nbEventsPerCardGate!=NULL) delete m2p_nbEventsPerCardGate;
  if (m2p_indexLastEventRespGate!= NULL) delete m2p_indexLastEventRespGate;
  if (m2p_indexLastEventCardGate!= NULL) delete m2p_indexLastEventCardGate;
  if (mp_currentFrameIndex!=NULL) delete mp_currentFrameIndex;
  if (mp_currentRespGateIndex!=NULL) delete mp_currentRespGateIndex;
  if (mp_currentCardGateIndex!=NULL) delete mp_currentCardGateIndex;
  if (mp_currentPMotionIndex!=NULL) delete mp_currentPMotionIndex;
  if (mp_listPMotionTriggers!=NULL) delete mp_listPMotionTriggers;
}

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/*
  \fn InitDynamicData
  \param a_nbRespGates
  \param a_nbCardGates
  \param a_pathTo4DDataFile : path to an ASCII file containing dynamic metadata regarding the acquisition
  \param a_rmCorrFlag : indicate whether respiratory motion correction is enabled (1) or disabled (0) 
  \param a_cmCorrFlag : indicate whether cardiac motion correction is enabled (1) or disabled (0) 
  \param a_pmCorrFlag : indicate whether involuntary patient motion correction is enabled (1) or disabled (0) 
  \brief Main function for instanciation and initialization of the member variables and arrays. Call the specific initialization function depending of the type of dataset.
  \todo  warning in the documentation that Respiratory motion correction is not supported for cardiac-gated data in the current implementation
  \return 0 if success, positive value otherwise.
*/
int oDynamicDataManager::InitDynamicData( int a_nbRespGates, int a_nbCardGates, const string& a_pathTo4DDataFile,
                                          int a_rmCorrFlag, int a_cmCorrFlag, int a_pmCorrFlag)
{
  if (m_verbose>=3) Cout("oDynamicDataManager::InitDynamicData() -> Initialize dynamic data management" << endl);

  // Initialization
  m_nbTimeFrames = mp_ID->GetNbTimeFrames();
  m_nbRespGates = a_nbRespGates;
  m_nbCardGates = a_nbCardGates;
  if (m_nbRespGates > 1) m_respGatingFlag = true;
  if (m_nbCardGates > 1) m_cardGatingFlag = true;
  m_rMotionCorrFlag = a_rmCorrFlag;
  m_cMotionCorrFlag = a_cmCorrFlag;
  m_pMotionCorrFlag = a_pmCorrFlag;
  
  // Instanciation & initialization for current indices (used during the loop on events to know which frame/gate the event belongs to)
  mp_currentFrameIndex     = new int[mp_ID->GetNbThreadsForProjection()];
  mp_currentRespGateIndex  = new int[mp_ID->GetNbThreadsForProjection()];
  mp_currentCardGateIndex  = new int[mp_ID->GetNbThreadsForProjection()];
  mp_currentPMotionIndex = new int[mp_ID->GetNbThreadsForProjection()];
  for (int th=0 ; th<mp_ID->GetNbThreadsForProjection() ; th++)
  {
    mp_currentFrameIndex    [0] = 0;
    mp_currentRespGateIndex [0] = 0;
    mp_currentCardGateIndex [0] = 0;
    mp_currentPMotionIndex[0] = 0;
  }
  
  // Instanciation & initialization of number of events per frame for gated reconstructions
  m2p_nbEventsPerRespGate = new int64_t*[m_nbTimeFrames];
  m2p_nbEventsPerCardGate = new int64_t*[m_nbTimeFrames];
  m2p_indexLastEventRespGate = new int64_t*[m_nbTimeFrames];
  m2p_indexLastEventCardGate = new int64_t*[m_nbTimeFrames];
  
  for (int fr=0; fr<m_nbTimeFrames; fr++)
  {
    m2p_nbEventsPerRespGate[fr] = new int64_t[m_nbRespGates];
    m2p_nbEventsPerCardGate[fr] = new int64_t[m_nbRespGates*m_nbCardGates];
    m2p_indexLastEventRespGate[fr] = new int64_t[m_nbRespGates];
    m2p_indexLastEventCardGate[fr] = new int64_t[m_nbRespGates*m_nbCardGates];
  
    for (int rg=0; rg<m_nbRespGates; rg++)
    {
      m2p_nbEventsPerRespGate[fr][rg] = -1;
      m2p_indexLastEventRespGate[fr][rg] = -1;
      
      for (int cg=0; cg<m_nbCardGates; cg++)
      {
        m2p_nbEventsPerCardGate[fr][rg*m_nbCardGates+cg] = -1;
        m2p_indexLastEventCardGate[fr][rg*m_nbCardGates+cg] = -1;
      }
    }
  }

  // Throw error if cardiac gating is enabled alongside respiratory motion correction (not available)
  // TODO : warning in the documentation that Respiratory motion correction is not supported for cardiac-gated data in the current implementation
  if (m_rMotionCorrFlag && m_cardGatingFlag)
  {
    Cerr("***** oDynamicDataManager::InitDynamicData()-> Respiratory motion correction is enabled for cardiac-gated data. This is not supported in the current implementation  !" << endl);
    return 1;
  }
    
  // Initialization for respiratory/cardiac gated reconstruction
  // Note : for Analytic Projection, gating flag could be enabled in order to project an image containing several gates, but no description file is required
  //        InitDynamicDataGating() is restricted to reconstruction
  //        Check on the existence of a_pathTo4DDataFile during reconstruction is performed onnly in Grecon
  if ((m_respGatingFlag || m_cardGatingFlag) && !a_pathTo4DDataFile.empty() )
  {
    if(m_verbose >=3) Cout("oDynamicDataManager::InitDynamicData()-> Initializing data for gated reconstruction... " << endl);
      
    if (InitDynamicDataGating(a_pathTo4DDataFile))
    {
      Cerr("***** oDynamicDataManager::InitDynamicData()-> A problem occured during the dynamic gating initialization !" << endl);
      return 1;
    }
  }

  // Initialization with involuntary patient motion corrected reconstruction
  if (m_pMotionCorrFlag && InitDynamicDataPatientMotion(a_pathTo4DDataFile) )
  {
    Cerr("***** oDynamicDataManager::InitDynamicData()-> A problem occured during the patient involuntary motion correction initialization !" << endl);
    return 1;
  }

  // Some feedback
  if (m_verbose>=3) 
  {
    if(m_respGatingFlag)  Cout("oDynamicDataManager::InitDynamicData()-> Respiratory gating enabled" << endl);
    if(m_rMotionCorrFlag) Cout("oDynamicDataManager::InitDynamicData()-> Respiratory image-based motion correction enabled" << endl);
    if(m_cardGatingFlag)  Cout("oDynamicDataManager::InitDynamicData()-> Cardiac gating enabled" << endl);
    if(m_cMotionCorrFlag) Cout("oDynamicDataManager::InitDynamicData()-> Cardiac image-based motion correction enabled" << endl);
    if(m_pMotionCorrFlag) Cout("oDynamicDataManager::InitDynamicData()-> Involuntary image-based patient motion correction enabled" << endl);
  }
    
  // End
  return 0;
}

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/*
  \fn InitDynamicDataGating
  \param a_pathToFile : path to an ASCII file containing dynamic metadata regarding the acquisition
  \brief Initialisation of arrays containing informations about the data splitting and respiratory/cardiac gated reconstruction
  \todo check the reconstruction with cardiac gated reconstruction. Some adjustements will be required for double gating
  \return 0 if success, positive value otherwise.
*/
int oDynamicDataManager::InitDynamicDataGating(const string& a_pathToFile)
{
  if(m_verbose >=3) Cout("oDynamicDataManager::InitDynamicDataGating() ... " << endl);
    
  // Respiratory gating enabled
  if (m_respGatingFlag)
  {
    // Read information about respiratory gating (number of events per respiratory gate per frame)
    if ( ReadDataASCIIFile(a_pathToFile, 
                          "respiratory_gates_data_splitting", 
                           m2p_nbEventsPerRespGate, 
                           m_nbRespGates, 
                           m_nbTimeFrames, 
                           KEYWORD_MANDATORY) )
    {
      Cerr("***** oDynamicDataManager::InitDynamicDataGating() -> Error while trying to read 'respiratory_gates_data_splitting' in file '" << a_pathToFile << "' !" << endl);
      return 1;
    }
    
    // Get the index of the last event of each respiratory gate using the number of events inside each gate
    uint64_t event_number_sum = 0;
    if (m_verbose>=3) Cout("oDynamicDataManager::InitDynamicDataGating() :" << endl);
            
    for (int fr=0; fr<m_nbTimeFrames; fr++)
      for (int rg=0; rg<m_nbRespGates; rg++)
      { 
        m2p_indexLastEventRespGate[fr][rg] += m2p_nbEventsPerRespGate[fr][rg] + event_number_sum;
        event_number_sum += m2p_nbEventsPerRespGate[fr][rg]; 
        if (m_verbose>=3) Cout("Number of events for frame #" << fr << ", respiratory gate #" << rg << " = " << m2p_nbEventsPerRespGate[fr][rg] << endl);
      } 
  }
  
  
  // Cardiac gating enabled
  if (m_cardGatingFlag)
  {
    // Read information about cardiac gating (number of events per cardiac gate per respiratory gates times frames)
    if ( ReadDataASCIIFile(a_pathToFile, 
                          "cardiac_gates_data_splitting", 
                           m2p_nbEventsPerCardGate,
                           m_nbCardGates, 
                           m_nbTimeFrames*m_nbRespGates, 
                           KEYWORD_MANDATORY) )
    {
      Cerr("***** oDynamicDataManager::InitDynamicDataGating() -> Error while trying to read 'cardiac_gates_data_splitting' in file '" << a_pathToFile << "' !" << endl);
      return 1;
    }
      
    // Get the index of the last event of each cardiac gate using the number of events inside each gate
    uint64_t event_number_sum = 0;
    if (m_verbose >=3) Cout("oDynamicDataManager::InitDynamicDataGating() :" << endl);
        
    for (int fr=0; fr<m_nbTimeFrames; fr++)
      for (int g=0; g<m_nbRespGates*m_nbCardGates; g++)
      { 
        m2p_indexLastEventCardGate[fr][g] += m2p_nbEventsPerCardGate[fr][g] + event_number_sum;
        event_number_sum += m2p_nbEventsPerCardGate[fr][g]; 
        if (m_verbose>=3) Cout("Number of events for frame #" << fr << ", cardiac gate #" << g << " = " << m2p_nbEventsPerCardGate[fr][g] << endl);
      } 
  }
  
  // End
  return 0;
}

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/*
  \fn InitDynamicDataPatientMotion
  \param a_pathToFile : path to an ASCII file containing dynamic metadata regarding the acquisition
  \brief Initialisation of involuntary patient motion correction information, if any.
  \todo Implementation currently IN PROGRESS. Will have to define how motion subset information is provided as it depends of each datafile, if the acquisition contain several bed steps.
  \return 0 if success, positive value otherwise.
*/
int oDynamicDataManager::InitDynamicDataPatientMotion(const string& a_pathToFile)
{
  if(m_verbose >=3) Cout("oDynamicDataManager::InitDynamicDataPatientMotion() ... " << endl);
  Cerr("!!!!! WARNING oDynamicDataManager::InitDynamicDataGating() -> Still WiP !" << endl);
  // First get the number of time triggers into the dynamic file
  if (ReadDataASCIIFile(a_pathToFile, 
                       "nb_involuntary_motion_triggers", 
                        &m_nbPMotionTriggers, 
                        1, 
                        KEYWORD_MANDATORY))
    {
      Cerr("***** oDynamicDataManager::InitDynamicDataPatientMotion() -> Involuntary motion correction enabled but could" << endl
        << " not find the number of triggers in the dynamic file '" << a_pathToFile << "' !" << endl);
      return 1;
    }
  
  // Allocate time triggers and read them from the dynamic file
  mp_listPMotionTriggers = (uint32_t*)malloc(m_nbPMotionTriggers*sizeof(uint32_t));

  if (ReadDataASCIIFile(a_pathToFile, 
                      "list_involuntary_motion_triggers", 
                        mp_listPMotionTriggers, 
                        m_nbPMotionTriggers, 
                        KEYWORD_MANDATORY))
  {
    Cerr("***** oDynamicDataManager::InitDynamicDataPatientMotion() -> Involuntary motion correction enabled but list of triggers" << endl
      << "                                                             not found in the dynamic file '" << a_pathToFile << "' !" << endl);
    return 1;
  }
  // End
  return 0;
}

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/*
  \fn SetDynamicSpecificQuantificationFactors
  \param FLTNB** a2p_quantificationFactors : 2 dimensional [timeframe][gate] set of quantitative factors to update
  \brief Compute gate-specific quantificative factors using the number of events within each gate, and update the quantitative factors passed in argument
  \return 0 if success, positive value otherwise.
*/
int oDynamicDataManager::SetDynamicSpecificQuantificationFactors(FLTNB** a2p_quantificationFactors)
{
  if(m_verbose >=3) Cout("oDynamicDataManager::SetDynamicSpecificQuantificationFactors() ... " << endl);
    
  // COMPUTE GATE-SPECIFIC QUANTITATIVE FACTORS
  if (m_nbRespGates>1 || m_nbCardGates>1)
  {
    for(int fr=0 ; fr<m_nbTimeFrames ; fr++)
    {
      // We have cardiac gates and don't correct for motion -> quantification factors required for cardiac gates
      if (m_cardGatingFlag && !m_cMotionCorrFlag)
      {
        uint64_t total_events_in_frame = 0;
        for(int g=0 ; g<m_nbRespGates*m_nbCardGates ; g++) total_events_in_frame += m2p_nbEventsPerCardGate[fr][g];

        if (m_verbose>=3) Cout("oDynamicDataManager::SetDynamicSpecificQuantificationFactors() -> Cardiac gating correction factors :" << endl);
        for(int g=0 ; g<m_nbRespGates*m_nbCardGates ; g++)
        {
          a2p_quantificationFactors[fr][g] *= (FLTNB)total_events_in_frame/(FLTNB)m2p_nbEventsPerCardGate[fr][g];
          if (m_verbose>=3) Cout("Frame #" << fr << ", cardiac gate #" << g << " = " << a2p_quantificationFactors[fr][g] << endl);
        }
      }
      
      // We have resp gates and don't correct for resp motion (and no independent cardiac gate reconstruction) -> quantification factors required for cardiac gates
      else if(m_respGatingFlag && !m_rMotionCorrFlag)
      {
        uint64_t total_events_in_frame = 0;
        for(int rg=0 ; rg<m_nbRespGates ; rg++) total_events_in_frame += m2p_nbEventsPerRespGate[fr][rg];

        if (m_verbose>=3) Cout("oDynamicDataManager::SetDynamicSpecificQuantificationFactors() -> Respiratory gating correction factors :" << endl);
        for(int g=0 ; g<m_nbRespGates*m_nbCardGates ; g++)
        {
          int rg = int(g/m_nbCardGates);
          a2p_quantificationFactors[fr][g] *= (FLTNB)total_events_in_frame/(FLTNB)m2p_nbEventsPerRespGate[fr][rg];
          if (m_verbose>=3) Cout("Frame #" << fr << ", gate #" << g << " = " << a2p_quantificationFactors[fr][g] << endl);
        }
      }
    }
  }
  
  // End
  return 0;
}

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int oDynamicDataManager::CheckParameters(int64_t a_nbEvents)
{
  if (m_verbose>=3) Cout("oDynamicDataManager::CheckParameters() -> Check parameters for dynamic data settings" << endl);
    
  // Check image dimensions
  if (mp_ID==NULL)
  {
    Cerr("***** oDynamicDataManager::CheckParameters() -> No image dimensions provided !" << endl);
    return 1;
  }
  // Check resp gates
  if (m_nbRespGates<0)
  {
    Cerr("***** oDynamicDataManager::CheckParameters() -> Wrong number of respiratory gates !" << endl);
    return 1;
  }
  // Check card gates
  if (m_nbCardGates<0)
  {
    Cerr("***** oDynamicDataManager::CheckParameters() -> Wrong number of respiratory gates !" << endl);
    return 1;
  }
  // Check involuntary motion triggers
  if (m_nbPMotionTriggers<0)
  {
    Cerr("***** oDynamicDataManager::CheckParameters() -> Wrong number of involuntary motion subsets provided !" << endl);
    return 1;
  }
  // Check verbosity
  if (m_verbose<0)
  {
    Cerr("***** oDynamicDataManager::CheckParameters() -> Wrong verbosity level provided !" << endl);
    return 1;
  }
  // Feedback regarding the enabled/disabled options for the reconstruction
  if (m_verbose>=2)
  {
    if (m_respGatingFlag) Cout("oDynamicDataManager::CheckParameters() -> Respiratory gating is enabled" << endl);
    if (m_rMotionCorrFlag) Cout("oDynamicDataManager::CheckParameters() -> Respiratory motion correction enabled" << endl);
    if (m_cardGatingFlag) Cout("oDynamicDataManager::CheckParameters() -> Cardiac gating is enabled" << endl);
    if (m_cMotionCorrFlag) Cout("oDynamicDataManager::CheckParameters() -> Cardiac motion correction is enabled" << endl);
    if (m_pMotionCorrFlag) Cout("oDynamicDataManager::CheckParameters() -> Involuntary motion correction is enabled" << endl);
  }

  // Check consistency between number of events in the datafile and the potential splitting of the dynamic data into respiratory or cardiac gates (if any gating is enabled)
  if (m_respGatingFlag)
  {
    int last_fr = m_nbTimeFrames-1;
    int last_rg = m_nbRespGates-1;
    if (m2p_indexLastEventRespGate[last_fr][last_rg]+1 != a_nbEvents)
    {
      Cerr("***** oDynamicDataManager::CheckParameters() -> Problem while checking consistency of dynamic data !" << endl
        << "                                                The number of events in the datafile (" << a_nbEvents
        << ") is different from the total number of events in respiratory gates (" << m2p_indexLastEventRespGate[last_fr][last_rg] << ") as initialized in the gating file !" << endl);
      return 1;
    }
  }
  if (m_cardGatingFlag)
  {
    int last_fr = m_nbTimeFrames-1;
    int last_rg = m_nbCardGates-1;
    if (m2p_indexLastEventCardGate[last_fr][last_rg]+1 != a_nbEvents)
    {
      Cerr("***** oDynamicDataManager::CheckParameters() -> Problem while checking consistency of dynamic data !" << endl
        << "                                                The number of events in the datafile (" << a_nbEvents
        << ") is different to the total number of events in cardiac gates (" << m2p_indexLastEventRespGate[last_fr][last_rg] << ") as initialized in the gating file !" << endl);
      return 1;
    }
  }
  
  // Normal end
  return 0;
}

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void oDynamicDataManager::ResetCurrentDynamicIndices()
{
  #ifdef CASTOR_VERBOSE
  if (m_verbose >=4) Cout("oDynamicDataManager::ResetCurrentDynamicIndices() -> Reset indices" << endl);
  #endif
  
  for (int th=0; th<mp_ID->GetNbThreadsForProjection(); th++)
  {
    // We initialize the frame index to -1 because at the beginning of the events loop, we don't know yet
    // if we are in the first frame (the user can reconstruct only a part of the whole datafile).
    mp_currentFrameIndex[th] = -1;
    mp_currentPMotionIndex[th] = 0;
    mp_currentRespGateIndex[th] = 0;
    mp_currentCardGateIndex[th] = 0;
  }
}

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/*
  \fn DynamicSwitch
  \param a_currentEventIndex : Index of the current event in the iterative reconstruction loop
  \param a_currentTime : Timestamp of the current event in the iterative reconstruction loop
  \param a_bed
  \param a_th
  \brief This function is called in the reconstruction event loop. It is used to check if the current event belongs to a new respiratory/cardiac/involuntary motion gate
         Increment the index reporting the current relative gate in this case
  \todo  Check implementation for cardiac gating and involuntary patient motion correction
  \return 0 if nothing to do,
          1 if the current timestamp is inferior to the start time of the first frame,
          2 if a deformation is required (gate has changed and motion correction is enabled)
*/
int oDynamicDataManager::DynamicSwitch(int64_t a_currentEventIndex, uint32_t a_currentTime, int a_bed, int a_th)
{
  #ifdef CASTOR_VERBOSE
  if (m_verbose >=4) Cout("oDynamicDataManager::DynamicSwitch() -> Enter function" << endl);
  #endif
  
  // The value that will be returned
  int return_value = DYNAMIC_SWITCH_NOTHING;

  // -------------------------------------------------------------------------------------------------
  // Step 1: involuntary motion management
  // -------------------------------------------------------------------------------------------------

  // Only do this if the involuntary motion correction is enabled (meaning we must proceed to a deformation)
  if (m_pMotionCorrFlag)
  {
    // Search if we passed one of the next motion triggers (starting at current index)
    for (int mt=mp_currentPMotionIndex[a_th]; mt<m_nbPMotionTriggers; mt++)
    {
      // If we passed this trigger, set the return value to DEFORMATION. However, we continue the loop
      // in the case where we passed multiple triggers.
      if (a_currentTime>=mp_listPMotionTriggers[mt])
      {
        mp_currentPMotionIndex[a_th] = mt+1;
        #ifdef CASTOR_VERBOSE
        if (m_verbose >=4) Cout("oDynamicDataManager::DynamicSwitch() -> Thread " << a_th << ", gate for patient motion correction switched to " << mp_currentPMotionIndex[a_th] << endl
                             << "                                        at event #" << a_currentEventIndex << ", timestamp = " << a_currentTime << endl);
        #endif
        return_value = DYNAMIC_SWITCH_DEFORMATION;
      }
    }
  }

  // -------------------------------------------------------------------------------------------------
  // Step 2: frame management
  // -------------------------------------------------------------------------------------------------

  // Special case if the frame number is still -1
  if (mp_currentFrameIndex[a_th]==-1)
  {
    // We check if we are before the first frame, in this case we directly return a CONTINUE signal to go to the next event
    if (a_currentTime<mp_ID->GetFrameTimeStartInMs(a_bed,0)) return DYNAMIC_SWITCH_CONTINUE;
    // Otherwise, we now are at least in the first frame (which will be updated right after this if section)
    else mp_currentFrameIndex[a_th] = 0;
  }

  // A boolean to know later if the frame index has changed
  bool frame_has_changed = false;

  // Now we search for the first frame index in which the event belongs, starting from the current frame index. Note that we do that
  // this way (not simply incrementing the frame index) because we want to deal with the case where the next event managed by this
  // thread could possibly skip multiple frames at once.
  for (int fr=mp_currentFrameIndex[a_th]; fr<m_nbTimeFrames; fr++)
  {
    // If the current time is less than the time stop of the frame 'fr', then the event belongs to this frame
    if (a_currentTime<mp_ID->GetFrameTimeStopInMs(a_bed,fr))
    {
      // Test if the frame has actually changed
      if (mp_currentFrameIndex[a_th]!=fr)
      {
        // Set the boolean to true
        frame_has_changed = true;
        // Update the current frame index
        mp_currentFrameIndex[a_th] = fr;
      }
      break;
    }
  }

  #ifdef CASTOR_VERBOSE
  if (frame_has_changed && m_verbose >=4)
    Cout("oDynamicDataManager::DynamicSwitch() -> Thread " << a_th << ", frame switched to " << mp_currentFrameIndex[a_th] << endl);
  #endif

  // -------------------------------------------------------------------------------------------------
  // Step 3: respiratory gating management
  // -------------------------------------------------------------------------------------------------

  // A boolean to know later if the respiratory index has changed
  bool resp_gate_has_changed = false;

  // Do this only if respiratory gating is enabled
  if (m_respGatingFlag)
  {
    // Test if the frame index has changed
    if (frame_has_changed)
    {
      // Reset the respiratory gate index
      mp_currentRespGateIndex[a_th] = 0;
      // No deformation signal need to be sent, as the forward/backward image matrices for the next frame will be in the reference position as required
    }
    // For this frame, search the first gate (from the current gate index) for which the provided event index is below the event-index-stop
    for (int rg=mp_currentRespGateIndex[a_th]; rg<m_nbRespGates; rg++)
    {
      // If the current event index is below the last event of this gate, then the event belongs to this gate
      // (We won't enter again in the if statement due to the flag setting to true)
      if (a_currentEventIndex<=m2p_indexLastEventRespGate[mp_currentFrameIndex[a_th]][rg] && resp_gate_has_changed == false)
      {
        // Test if the gate has actually changed
        if (mp_currentRespGateIndex[a_th]!=rg)
        {
          // Update the current gate index
          mp_currentRespGateIndex[a_th] = rg;
          // Verbose
          #ifdef CASTOR_VERBOSE
          if (m_verbose>=4) Cout("oDynamicDataManager::DynamicSwitch() -> Thread " << a_th << ", respiratory gate switch to " << mp_currentRespGateIndex[a_th]
                                                                                   << " on event " << a_currentEventIndex << endl
                                                                                   << "current frame : " << mp_currentFrameIndex[a_th] << endl
                                                                                   << "current respiratory gate index " << mp_currentRespGateIndex[a_th] << endl);
          #endif
          // If motion correction is enabled, then we should return a DEFORMATION signal
          if (m_rMotionCorrFlag) return_value = DYNAMIC_SWITCH_DEFORMATION;
        }
        // Set the boolean to true
        resp_gate_has_changed = true;
      }
    }
  }
  
  // -------------------------------------------------------------------------------------------------
  // Step 4: cardiac gating management
  // -------------------------------------------------------------------------------------------------

  // A boolean to know later if the respiratory index has changed
  bool card_gate_has_changed = false;
  
  // Do this only if cardiac gating is enabled
  if (m_cardGatingFlag)
  {
    // Test if the frame or respiratory index have changed
    if (frame_has_changed || resp_gate_has_changed)
    {
      // Reset the cardiac gate index
      mp_currentCardGateIndex[a_th] = 0;
      // Thus if one apply cardiac motion correction, we should return a DEFORMATION signal
      if (m_cMotionCorrFlag) return_value = DYNAMIC_SWITCH_DEFORMATION;
    }
    // For this frame and respiratory gate, search the first gate (from the current gate index) for which the provided event index is below the event-index-stop
    for (int cg=mp_currentCardGateIndex[a_th]; cg<m_nbCardGates; cg++)
    {
      // If the current event index is below the event-index-stop of this gate, then the event belongs to this gate
      if (a_currentEventIndex<m2p_indexLastEventCardGate[mp_currentFrameIndex[a_th]][mp_currentRespGateIndex[a_th]*m_nbCardGates+cg]  && card_gate_has_changed == false)
      {
        // Test if the gate has actually changed
        if (mp_currentCardGateIndex[a_th]!=cg)
        {
          // Update the current gate index
          mp_currentCardGateIndex[a_th] = cg;
          // Verbose
          #ifdef CASTOR_VERBOSE
          if (m_verbose>=4) Cout("oDynamicDataManager::DynamicSwitch() -> Thread " << a_th << ", cardiac gate switch to " <<  mp_currentCardGateIndex[a_th]
                                                                                   << " on event " << a_currentEventIndex << endl
                                                                                   << "current frame : " << mp_currentFrameIndex[a_th] << endl);
          #endif
          // If motion correction is enabled, then we should return a DEFORMATION signal
          if (m_cMotionCorrFlag) return_value = DYNAMIC_SWITCH_DEFORMATION;
        }
        // Set the boolean to true
        card_gate_has_changed = true;
      }
    }
  }
  
  // -------------------------------------------------------------------------------------------------
  // Step 5: just return the value !
  // -------------------------------------------------------------------------------------------------

  // Return the status of the dynamic switch
  return return_value;
}