r573: no message

[ctsim.git] / libctsim / filter.cpp

diff --git a/libctsim/filter.cpp b/libctsim/filter.cpp
index 60f97c8e9b7f27319a3fc1a0dcb088f06e360b00..f86478653bbf4d93a814c66a51db717b93d289be 100644 (file)
--- a/libctsim/filter.cpp
+++ b/libctsim/filter.cpp
@@ -7,9 +7,9 @@
 **     Date Started:           Aug 1984
 **
 **  This is part of the CTSim program
-**  Copyright (C) 1983-2000 Kevin Rosenberg
+**  Copyright (c) 1983-2000 Kevin Rosenberg
 **
-**  $Id: filter.cpp,v 1.33 2001/01/02 16:02:13 kevin Exp $
+**  $Id: filter.cpp,v 1.38 2001/02/22 18:22:40 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
@@ -30,39 +30,47 @@
 int SignalFilter::N_INTEGRAL=500;  //static member
 
 const int SignalFilter::FILTER_INVALID = -1 ;
-const int SignalFilter::FILTER_ABS_BANDLIMIT = 0;      // filter times |x = |
+const int SignalFilter::FILTER_ABS_BANDLIMIT = 0;      // filter times |x|
 const int SignalFilter::FILTER_ABS_G_HAMMING = 1;
-const int SignalFilter::FILTER_ABS_COSINE = 2;
-const int SignalFilter::FILTER_ABS_SINC = 3;
-const int SignalFilter::FILTER_SHEPP = 4;
-const int SignalFilter::FILTER_BANDLIMIT = 5;
-const int SignalFilter::FILTER_SINC = 6;
-const int SignalFilter::FILTER_G_HAMMING = 7;
-const int SignalFilter::FILTER_COSINE = 8;
-const int SignalFilter::FILTER_TRIANGLE = 9;
-
-const char* SignalFilter::s_aszFilterName[] = {
+const int SignalFilter::FILTER_ABS_HANNING = 2;
+const int SignalFilter::FILTER_ABS_COSINE = 3;
+const int SignalFilter::FILTER_ABS_SINC = 4;
+const int SignalFilter::FILTER_SHEPP = 5;
+const int SignalFilter::FILTER_BANDLIMIT = 6;
+const int SignalFilter::FILTER_SINC = 7;
+const int SignalFilter::FILTER_G_HAMMING = 8;
+const int SignalFilter::FILTER_HANNING = 9;
+const int SignalFilter::FILTER_COSINE = 10;
+const int SignalFilter::FILTER_TRIANGLE = 11;
+
+const int SignalFilter::s_iReconstructFilterCount = 4;
+
+const char* const SignalFilter::s_aszFilterName[] = {
   {"abs_bandlimit"},
   {"abs_hamming"},
+  {"abs_hanning"},
   {"abs_cosine"},
-  {"abs_sinc"},
   {"shepp"},
+  {"abs_sinc"},
   {"bandlimit"},
   {"sinc"},
   {"hamming"},
+  {"hanning"},
   {"cosine"},
   {"triangle"},
 };
 
-const char* SignalFilter::s_aszFilterTitle[] = {
+const char* const SignalFilter::s_aszFilterTitle[] = {
   {"Abs(w) * Bandlimit"},
   {"Abs(w) * Hamming"},
+  {"Abs(w) * Hanning"},
   {"Abs(w) * Cosine"},
-  {"Abs(w) * Sinc"},
   {"Shepp"},
+  {"Abs(w) * Sinc"},
   {"Bandlimit"},
   {"Sinc"},
   {"Hamming"},
+  {"Hanning"},
   {"Cosine"},
   {"Triangle"},
 };
@@ -74,12 +82,12 @@ const int SignalFilter::DOMAIN_INVALID = -1;
 const int SignalFilter::DOMAIN_FREQUENCY = 0;
 const int SignalFilter::DOMAIN_SPATIAL = 1;
     
-const char* SignalFilter::s_aszDomainName[] = {
+const char* const SignalFilter::s_aszDomainName[] = {
   {"frequency"},
   {"spatial"},
 };
 
-const char* SignalFilter::s_aszDomainTitle[] = {
+const char* const SignalFilter::s_aszDomainTitle[] = {
   {"Frequency"},
   {"Spatial"},
 };
@@ -437,12 +445,18 @@ SignalFilter::frequencyResponse (int filterID, double bw, double u, double param
   case FILTER_ABS_SINC:
     q = au * bw * sinc (PI * bw * u, 1.);
     break;
+  case FILTER_HANNING:
+    param = 0.54; 
+    // follow through to G_HAMMING
   case FILTER_G_HAMMING:
     if (fabs(au) >= fabs(bw / 2) + F_EPSILON)
       q = 0;
     else
       q = param + (1 - param) * cos (TWOPI * u / bw);
     break;
+  case FILTER_ABS_HANNING:
+    param = 0.54;
+    // follow through to ABS_G_HAMMING
   case FILTER_ABS_G_HAMMING:
     if (fabs(au) >= fabs(bw / 2) + F_EPSILON)
       q = 0;
@@ -489,9 +503,11 @@ SignalFilter::haveAnalyticSpatial (int filterID)
   case FILTER_TRIANGLE:
   case FILTER_COSINE:
   case FILTER_G_HAMMING:
+  case FILTER_HANNING:
   case FILTER_ABS_BANDLIMIT:
   case FILTER_ABS_COSINE:
   case FILTER_ABS_G_HAMMING:
+  case FILTER_ABS_HANNING:
   case FILTER_SHEPP:
   case FILTER_SINC:
     haveAnalytic = true;
@@ -523,6 +539,9 @@ SignalFilter::spatialResponseAnalytic (int filterID, double bw, double x, double
   case FILTER_COSINE:
     q = sinc(b-u,w) + sinc(b+u,w);
     break;
+  case FILTER_HANNING:
+    param = 0.54;
+    // follow through to G_HAMMING
   case FILTER_G_HAMMING:
     q = 2 * param * sin(u*w)/u + (1-param) * (sinc(b2-u, w) + sinc(b2+u, w));
     break;
@@ -532,6 +551,9 @@ SignalFilter::spatialResponseAnalytic (int filterID, double bw, double x, double
   case FILTER_ABS_COSINE:
     q = integral_abscos(b-u,w) + integral_abscos(b+u,w);
     break;
+  case FILTER_ABS_HANNING:
+    param = 0.54;
+    // follow through to ABS_G_HAMMING
   case FILTER_ABS_G_HAMMING:
     q = 2 * param * integral_abscos(u,w) +
       (1-param)*(integral_abscos(u-b2,w)+integral_abscos(u+b2,w));
@@ -559,30 +581,21 @@ SignalFilter::spatialResponseAnalytic (int filterID, double bw, double x, double
 }
 
 
-/* NAME
- *   sinc                      Return sin(x)/x function
- *
- * SYNOPSIS
- *   v = sinc (x, mult)
- *   double v                  sinc value
- *   double x, mult
- *
- * DESCRIPTION
- *   v = sin(x * mult) / x;
- */
 
+// Functions that are inline in filter.h
+
+
+//  sinc                       Return sin(x)/x function 
+//   v = sinc (x, mult)
+// Calculates sin(x * mult) / x;
+
+//  integral_abscos    Returns integral of u*cos(u)
+//
+//   q = integral_abscos (u, w)
+//   double q                  Integral value
+//   double u                  Integration variable
+//   double w                  Upper integration boundary
+// Returns the value of integral of u*cos(u)*dV for V = 0 to w
 
-/* NAME
- *   integral_abscos                   Returns integral of u*cos(u)
- *
- * SYNOPSIS
- *   q = integral_abscos (u, w)
- *   double q                  Integral value
- *   double u                  Integration variable
- *   double w                  Upper integration boundary
- *
- * DESCRIPTION
- *   Returns the value of integral of u*cos(u)*dV for V = 0 to w
- */