r640: no message

[ctsim.git] / libctsim / procsignal.cpp

diff --git a/libctsim/procsignal.cpp b/libctsim/procsignal.cpp
index 32af552ca5f63d7398e71641d9583d349ab8d1e6..2d6600d37e6b60767bd416e05c216a494416ec24 100644 (file)
--- a/libctsim/procsignal.cpp
+++ b/libctsim/procsignal.cpp
@@ -9,7 +9,7 @@
 **  This is part of the CTSim program
 **  Copyright (c) 1983-2001 Kevin Rosenberg
 **
-**  $Id: procsignal.cpp,v 1.24 2001/01/28 19:10:18 kevin Exp $
+**  $Id: procsignal.cpp,v 1.29 2001/03/18 18:08:25 kevin Exp $
 **
 **  This program is free software; you can redistribute it and/or modify
 **  it under the terms of the GNU General Public License (version 2) as
@@ -41,17 +41,17 @@ const int ProcessSignal::FILTER_METHOD_FFT = 3;
 const int ProcessSignal::FILTER_METHOD_FFTW = 4;
 const int ProcessSignal::FILTER_METHOD_RFFTW =5 ;
 #endif
-const char* ProcessSignal::s_aszFilterMethodName[] = {
+const char* const ProcessSignal::s_aszFilterMethodName[] = {
   {"convolution"},
   {"fourier"},
-  {"fouier_table"},
+  {"fouier-table"},
   {"fft"},
 #if HAVE_FFTW
   {"fftw"},
   {"rfftw"},
 #endif
 };
-const char* ProcessSignal::s_aszFilterMethodTitle[] = {
+const char* const ProcessSignal::s_aszFilterMethodTitle[] = {
   {"Convolution"},
   {"Fourier"},
   {"Fouier Trigometric Table"},
@@ -67,11 +67,11 @@ const int ProcessSignal::s_iFilterMethodCount = sizeof(s_aszFilterMethodName) /
 const int ProcessSignal::FILTER_GENERATION_INVALID = -1;
 const int ProcessSignal::FILTER_GENERATION_DIRECT = 0;
 const int ProcessSignal::FILTER_GENERATION_INVERSE_FOURIER = 1;
-const char* ProcessSignal::s_aszFilterGenerationName[] = {
+const char* const ProcessSignal::s_aszFilterGenerationName[] = {
   {"direct"},
-  {"inverse_fourier"},
+  {"inverse-fourier"},
 };
-const char* ProcessSignal::s_aszFilterGenerationTitle[] = {
+const char* const ProcessSignal::s_aszFilterGenerationTitle[] = {
   {"Direct"},
   {"Inverse Fourier"},
 };
@@ -84,7 +84,7 @@ const int ProcessSignal::s_iFilterGenerationCount = sizeof(s_aszFilterGeneration
 ProcessSignal::ProcessSignal (const char* szFilterName, const char* szFilterMethodName, double dBandwidth, 
                               double dSignalIncrement, int nSignalPoints, double dFilterParam, const char* szDomainName, 
                               const char* szFilterGenerationName, int iZeropad, int iPreinterpolationFactor, int iTraceLevel, 
-                              int iGeometry, double dFocalLength, SGP* pSGP)
+                              int iGeometry, double dFocalLength, double dSourceDetectorLength, SGP* pSGP)
                               : m_adFourierCosTable(NULL), m_adFourierSinTable(NULL), m_adFilter(NULL), m_fail(false)
 {
   m_idFilterMethod = convertFilterMethodNameToID (szFilterMethodName);
@@ -117,7 +117,8 @@ ProcessSignal::ProcessSignal (const char* szFilterName, const char* szFilterMeth
   }
   
   init (m_idFilter, m_idFilterMethod, dBandwidth, dSignalIncrement, nSignalPoints, dFilterParam, m_idDomain, 
-    m_idFilterGeneration, iZeropad, iPreinterpolationFactor, iTraceLevel, iGeometry, dFocalLength, pSGP);
+    m_idFilterGeneration, iZeropad, iPreinterpolationFactor, iTraceLevel, iGeometry, dFocalLength, 
+    dSourceDetectorLength, pSGP);
 }
 
 
@@ -125,7 +126,7 @@ void
 ProcessSignal::init (const int idFilter, const int idFilterMethod, double dBandwidth, double dSignalIncrement, 
                      int nSignalPoints, double dFilterParam, const int idDomain, const int idFilterGeneration, 
                      const int iZeropad, const int iPreinterpolationFactor, int iTraceLevel, int iGeometry, 
-                     double dFocalLength, SGP* pSGP)
+                     double dFocalLength, double dSourceDetectorLength, SGP* pSGP)
 {
   int i;
   m_idFilter = idFilter;
@@ -134,6 +135,7 @@ ProcessSignal::init (const int idFilter, const int idFilterMethod, double dBandw
   m_idFilterGeneration = idFilterGeneration;
   m_idGeometry = iGeometry;
   m_dFocalLength = dFocalLength;
+  m_dSourceDetectorLength = dSourceDetectorLength;
   
   if (m_idFilter == SignalFilter::FILTER_INVALID || m_idDomain == SignalFilter::DOMAIN_INVALID || m_idFilterMethod == FILTER_METHOD_INVALID || m_idFilterGeneration == FILTER_GENERATION_INVALID) {
     m_fail = true;
@@ -149,12 +151,12 @@ ProcessSignal::init (const int idFilter, const int idFilterMethod, double dBandw
   m_iZeropad = iZeropad;
   m_iPreinterpolationFactor = iPreinterpolationFactor;
   
-  // scale signalInc/BW to signalInc/2 to adjust for imaginary detector
-  // through origin of phantom rather than 2 times distance to detector, 
+  // scale signalInc/BW to adjust for imaginary detector through origin of phantom 
   // see Kak-Slaney Fig 3.22, for Collinear diagram
   if (m_idGeometry == Scanner::GEOMETRY_EQUILINEAR) {
-    m_dSignalInc /= 2;
-    m_dBandwidth *= 2;
+    double dEquilinearScale = m_dSourceDetectorLength / m_dFocalLength;
+    m_dSignalInc /= dEquilinearScale;
+    m_dBandwidth *= dEquilinearScale;
   }
   
   if (m_idFilterMethod == FILTER_METHOD_FFT) {
@@ -256,22 +258,10 @@ ProcessSignal::init (const int idFilter, const int idFilterMethod, double dBandw
     
     if (m_idFilterGeneration == FILTER_GENERATION_DIRECT) {
       // calculate number of filter points with zeropadding
-      m_nFilterPoints = m_nSignalPoints;
-      if (m_iZeropad > 0) {
-        double logBase2 = log(m_nFilterPoints) / log(2);
-        int nextPowerOf2 = static_cast<int>(floor(logBase2));
-        if (logBase2 != floor(logBase2))
-          nextPowerOf2++;
-        nextPowerOf2 += (m_iZeropad - 1);
-        m_nFilterPoints = 1 << nextPowerOf2;
-#if defined(DEBUG) || defined(_DEBUG)
-        if (m_traceLevel >= Trace::TRACE_CONSOLE)
-          sys_error (ERR_TRACE, "nFilterPoints = %d", m_nFilterPoints);
-#endif
-      }
+      m_nFilterPoints = addZeropadFactor (m_nSignalPoints, m_iZeropad);
       m_nOutputPoints = m_nFilterPoints * m_iPreinterpolationFactor;
       
-      if (m_nFilterPoints % 2) { // Odd
+      if (isOdd (m_nFilterPoints)) { // Odd
         m_dFilterMin = -1. / (2 * m_dSignalInc);
         m_dFilterMax = 1. / (2 * m_dSignalInc);
         m_dFilterInc = (m_dFilterMax - m_dFilterMin) / (m_nFilterPoints - 1);
@@ -295,7 +285,7 @@ ProcessSignal::init (const int idFilter, const int idFilterMethod, double dBandw
         dlgEZPlot.ShowModal();
       }
 #endif
-
+      
       // This works fairly well. I'm not sure why since scaling for geometries is done on
       // frequency filter rather than spatial filter as it should be.
       // It gives values slightly off than freq/inverse filtering
@@ -327,9 +317,9 @@ ProcessSignal::init (const int idFilter, const int idFilterMethod, double dBandw
         dlgEZPlot.ShowModal();
       }
 #endif
-
+      
       // FILTERING:  FREQUENCY - INVERSE FOURIER
-
+      
     } else if (m_idFilterGeneration == FILTER_GENERATION_INVERSE_FOURIER) {
       // calculate number of filter points with zeropadding
       int nSpatialPoints = 2 * (m_nSignalPoints - 1) + 1;
@@ -874,3 +864,17 @@ ProcessSignal::finiteFourierTransform (const std::complex<double> input[], doubl
   }
 }
 
+
+int
+ProcessSignal::addZeropadFactor (int n, int iZeropad)
+{
+  if (iZeropad > 0) {
+    double dLogBase2 = log(n) / log(2);
+    int iLogBase2 = static_cast<int>(floor (dLogBase2));
+    if (dLogBase2 != floor(dLogBase2))
+      iLogBase2++;   // raise up to next power of 2
+    n = 1 << (iLogBase2 + (iZeropad - 1));
+  }
+
+  return n;
+}