Version 4.4.0

src/Fir.cpp

@@ -0,0 +1,73 @@
+/***************************************************/
+/*! \class Fir
+    \brief STK general finite impulse response filter class.
+
+    This class provides a generic digital filter structure that can be
+    used to implement FIR filters.  For filters with feedback terms,
+    the Iir class should be used.
+
+    In particular, this class implements the standard difference
+    equation:
+
+    y[n] = b[0]*x[n] + ... + b[nb]*x[n-nb]
+
+    The \e gain parameter is applied at the filter input and does not
+    affect the coefficient values.  The default gain value is 1.0.
+    This structure results in one extra multiply per computed sample,
+    but allows easy control of the overall filter gain.
+
+    by Perry R. Cook and Gary P. Scavone, 1995 - 2009.
+*/
+/***************************************************/
+
+#include "Fir.h"
+
+namespace stk {
+
+Fir :: Fir()
+{
+  // The default constructor should setup for pass-through.
+  b_.push_back( 1.0 );
+
+  inputs_.resize( 1, 1, 0.0 );
+}
+
+Fir :: Fir( std::vector<StkFloat> &coefficients )
+{
+  // Check the arguments.
+  if ( coefficients.size() == 0 ) {
+    errorString_ << "Fir: coefficient vector must have size > 0!";
+    handleError( StkError::FUNCTION_ARGUMENT );
+  }
+
+  gain_ = 1.0;
+  b_ = coefficients;
+
+  inputs_.resize( b_.size(), 1, 0.0 );
+  this->clear();
+}
+
+Fir :: ~Fir()
+{
+}
+
+void Fir :: setCoefficients( std::vector<StkFloat> &coefficients, bool clearState )
+{
+  // Check the argument.
+  if ( coefficients.size() == 0 ) {
+    errorString_ << "Fir::setCoefficients: coefficient vector must have size > 0!";
+    handleError( StkError::FUNCTION_ARGUMENT );
+  }
+
+  if ( b_.size() != coefficients.size() ) {
+    b_ = coefficients;
+    inputs_.resize( b_.size(), 1, 0.0 );
+  }
+  else {
+    for ( unsigned int i=0; i<b_.size(); i++ ) b_[i] = coefficients[i];
+  }
+
+  if ( clearState ) this->clear();
+}
+
+} // stk namespace