NormalizingBiQuadFilterDF1< T > Class Template Reference

#include <Filters/BiQuad.hpp>

Detailed Description

template<class T>
class NormalizingBiQuadFilterDF1< T >

BiQuad filter Direct Form 1 implementation that normalizes the coefficients upon initialization.

This class is faster than NonNormalizingBiQuadFilterDF1, because each filter iteration involves only addition and multiplication, no divisions.
It works great for floating point numbers, but might be less ideal for integer types, because it can create large rounding errors on the coefficients.

Implements the following difference equation:

\[ y[n] = \frac{b_0 \cdot x[n] + b_1 \cdot x[n-1] + b_2 \cdot x[n-2] - a_1 \cdot y[n-1] - a_2 \cdot y[n-2]}{a_0} \]

Definition at line 39 of file BiQuad.hpp.

Collaboration diagram for NormalizingBiQuadFilterDF1< T >:

Public Member Functions
	NormalizingBiQuadFilterDF1 ()=default
	NormalizingBiQuadFilterDF1 (const AH::Array< T, 3 > &b, const AH::Array< T, 3 > &a)
	NormalizingBiQuadFilterDF1 (const BiQuadCoefficients< T > &coefficients)
	NormalizingBiQuadFilterDF1 (const AH::Array< T, 3 > &b, const AH::Array< T, 3 > &a, T gain)
	NormalizingBiQuadFilterDF1 (const BiQuadCoefficients< T > &coefficients, T gain)
T	operator() (T input)
	Update the internal state with the new input \( x[n] \) and return the new output \( y[n] \). More...

Static Public Member Functions
template<bool Enable = true>
static std::enable_if_t< std::is_floating_point< T >::value &&Enable, T >	update (T input, AH::Array< T, 2 > &x, AH::Array< T, 2 > &y, const AH::Array< T, 3 > &b, const AH::Array< T, 2 > &a)
template<bool Enable = true>
static std::enable_if_t<!std::is_floating_point< T >::value &&Enable, T >	update (T input, AH::Array< T, 2 > &x, AH::Array< T, 2 > &y, const AH::Array< T, 3 > &b, const AH::Array< T, 2 > &a)

Private Attributes
AH::Array< T, 2 >	x = {{}}
	Previous inputs. More...
AH::Array< T, 2 >	y = {{}}
	Previous outputs. More...
AH::Array< T, 3 >	b = {{}}
	Numerator coefficients. More...
AH::Array< T, 2 >	a = {{}}
	Denominator coefficients. More...

Constructor & Destructor Documentation

NormalizingBiQuadFilterDF1() [1/5]

NormalizingBiQuadFilterDF1 ( )

default

NormalizingBiQuadFilterDF1() [2/5]

NormalizingBiQuadFilterDF1 ( const AH::Array< T, 3 > &  b, const AH::Array< T, 3 > &  a  )

inline

Definition at line 43 of file BiQuad.hpp.

NormalizingBiQuadFilterDF1() [3/5]

NormalizingBiQuadFilterDF1 ( const BiQuadCoefficients< T > &  coefficients )

inline

Definition at line 47 of file BiQuad.hpp.

NormalizingBiQuadFilterDF1() [4/5]

NormalizingBiQuadFilterDF1 ( const AH::Array< T, 3 > &  b, const AH::Array< T, 3 > &  a, T  gain  )

inline

Definition at line 50 of file BiQuad.hpp.

NormalizingBiQuadFilterDF1() [5/5]

NormalizingBiQuadFilterDF1 ( const BiQuadCoefficients< T > &  coefficients, T  gain  )

inline

Definition at line 54 of file BiQuad.hpp.

Member Function Documentation

update() [1/2]

static std::enable_if_t< std::is_floating_point< T >::value &&Enable, T > update ( T  input, AH::Array< T, 2 > &  x, AH::Array< T, 2 > &  y, const AH::Array< T, 3 > &  b, const AH::Array< T, 2 > &  a  )

inlinestatic

Definition at line 60 of file BiQuad.hpp.

update() [2/2]

static std::enable_if_t<!std::is_floating_point< T >::value &&Enable, T > update ( T  input, AH::Array< T, 2 > &  x, AH::Array< T, 2 > &  y, const AH::Array< T, 3 > &  b, const AH::Array< T, 2 > &  a  )

inlinestatic

Definition at line 76 of file BiQuad.hpp.

operator()()

T operator() ( T  input )

inline

Update the internal state with the new input \( x[n] \) and return the new output \( y[n] \).

Parameters

input

The new input \( x[n] \).

Returns

The new output \( y[n] \).

Definition at line 98 of file BiQuad.hpp.

Member Data Documentation

x

AH::Array<T, 2> x = {{}}

private

Previous inputs.

Definition at line 101 of file BiQuad.hpp.

y

AH::Array<T, 2> y = {{}}

private

Previous outputs.

Definition at line 102 of file BiQuad.hpp.

b

AH::Array<T, 3> b = {{}}

private

Numerator coefficients.

Definition at line 103 of file BiQuad.hpp.

a

AH::Array<T, 2> a = {{}}

private

Denominator coefficients.

Definition at line 104 of file BiQuad.hpp.

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The documentation for this class was generated from the following file:

• BiQuad.hpp