cannam@0: /* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */
cannam@0: 
cannam@0: /*
cannam@0:     QM DSP Library
cannam@0: 
cannam@0:     Centre for Digital Music, Queen Mary, University of London.
cannam@0:     This file copyright 2005-2006 Christian Landone.
cannam@0:     All rights reserved.
cannam@0: */
cannam@0: 
cannam@0: #include "Filter.h"
cannam@0: 
cannam@0: //////////////////////////////////////////////////////////////////////
cannam@0: // Construction/Destruction
cannam@0: //////////////////////////////////////////////////////////////////////
cannam@0: 
cannam@0: Filter::Filter( FilterConfig Config )
cannam@0: {
cannam@0:     m_ord = 0;
cannam@0:     m_outBuffer = NULL;
cannam@0:     m_inBuffer = NULL;
cannam@0: 
cannam@0:     initialise( Config );
cannam@0: }
cannam@0: 
cannam@0: Filter::~Filter()
cannam@0: {
cannam@0:     deInitialise();
cannam@0: }
cannam@0: 
cannam@0: void Filter::initialise( FilterConfig Config )
cannam@0: {
cannam@0:     m_ord = Config.ord;
cannam@0:     m_ACoeffs = Config.ACoeffs;
cannam@0:     m_BCoeffs = Config.BCoeffs;
cannam@0: 
cannam@0:     m_inBuffer = new double[ m_ord + 1 ];
cannam@0:     m_outBuffer = new double[ m_ord + 1 ];
cannam@0: 
cannam@0:     reset();
cannam@0: }
cannam@0: 
cannam@0: void Filter::deInitialise()
cannam@0: {
cannam@0:     delete[] m_inBuffer;
cannam@0:     delete[] m_outBuffer;
cannam@0: }
cannam@0: 
cannam@0: void Filter::reset()
cannam@0: {
cannam@0:     for( unsigned int i = 0; i < m_ord+1; i++ ){ m_inBuffer[ i ] = 0.0; }
cannam@0:     for(unsigned int  i = 0; i < m_ord+1; i++ ){ m_outBuffer[ i ] = 0.0; }
cannam@0: }
cannam@0: 
cannam@0: void Filter::process( double *src, double *dst, unsigned int length )
cannam@0: {
cannam@0:     unsigned int SP,i,j;
cannam@0: 
cannam@0:     double xin,xout;
cannam@0: 
cannam@0:     for (SP=0;SP<length;SP++)
cannam@0:     {
cannam@0:         xin=src[SP];
cannam@0:         /* move buffer */
cannam@0:         for ( i = 0; i < m_ord; i++) {m_inBuffer[ m_ord - i ]=m_inBuffer[ m_ord - i - 1 ];}
cannam@0:         m_inBuffer[0]=xin;
cannam@0: 
cannam@0:         xout=0.0;
cannam@0:         for (j=0;j< m_ord + 1; j++)
cannam@0: 	    xout = xout + m_BCoeffs[ j ] * m_inBuffer[ j ];
cannam@0:         for (j = 0; j < m_ord; j++)
cannam@0: 	    xout= xout - m_ACoeffs[ j + 1 ] * m_outBuffer[ j ];
cannam@0: 
cannam@0:         dst[ SP ] = xout;
cannam@0:         for ( i = 0; i < m_ord - 1; i++ ) { m_outBuffer[ m_ord - i - 1 ] = m_outBuffer[ m_ord - i - 2 ];}
cannam@0:         m_outBuffer[0]=xout;
cannam@0: 
cannam@0:     } /* end of SP loop */
cannam@0: }
cannam@0: 
cannam@0: 
cannam@0: