SPUC::iir_allpass1_halfband< Numeric, Coeff > Class Template Reference
[SPUC double templates, IIR filters]

Template Class for Allpass halfband IIR Filter. More...

#include <iir_allpass1_halfband.h>

Collaboration diagram for SPUC::iir_allpass1_halfband< Numeric, Coeff >:


Public Member Functions
	iir_allpass1_halfband (Coeff c0, Coeff c1, long round_bits=0)
void	reset ()
	reset
Numeric	clock (Numeric input)
	Shift inputs by one time sample and place new sample into array.
char	ready (void)
Public Attributes
char	even
Protected Attributes
allpass_1< Numeric, Coeff >	A0
	The 2 1st order allpass filters.
allpass_1< Numeric, Coeff >	A1
Numeric	out0
	Individual filter outputs.
Numeric	out1

Detailed Description

template<class Numeric, class Coeff = float_type>
class SPUC::iir_allpass1_halfband< Numeric, Coeff >

Template Class for Allpass halfband IIR Filter.

The filter is a combination of 2 Allpass sections of the form G(z) = (a*z*z + 1)/(z*z+a) so that the overall H(z) is H(z) = 1/z*G(z,a0) + G(z,a1) The combination of these two allpass functions result in a lowpass/highpass complementary pair. The class only uses the low pass filter. This is similar to allpass_iir, except since this is used as a halfband filter the output samples are decimated by 2. So that if the member function clock is called at the higher (input) sampling rate, the outputs are only valid even second sample. This is taken advantage off by running the individual sections effectively at the lower rate. The invalid samples are set to zero. This class needs the allpass_1 class